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DALTON FULL PAPER J. Chem. Soc. Dalton Trans. 1999 2627–2631 2627 Reactions of an antimony containing cage compound with metal carbonyls synthesis and structural characterization of [{M(CO)5}2(1 :1-P4Sb2C4But 4)] M Cr Mo or W and [{Fe(CO)4}2{Fe(CO)3(3 :1-P4Sb2C4But 4)}] David E. Hibbs Michael B. Hursthouse Cameron Jones * and Ryan C. Thomas Department of Chemistry University of Wales Cardi. P.O. Box 912 Park Place Cardi. UK CF1 3TB Received 20th April 1999 Accepted 23rd June 1999 The antimony containing cage compound P4Sb2C4But 4 was treated with an excess of [M(CO)5(THF)] M = Cr Mo or W to produce the 2 1 adduct complexes [{M(CO)5}2(.1 :.1-P4Sb2C4But 4)] which X-ray crystallographic studies have shown to contain one M(CO)5 fragment co-ordinated to an unsaturated phosphorus centre and one co-ordinated to an antimony centre.In contrast its reaction with an excess of [Fe2(CO)9] produced [{Fe(CO)4}2{Fe(CO)3(.3 :.1-P4Sb2C4But 4)}] which is probably formed by the insertion of an Fe(CO)3 fragment into an Sb–P bond of the cage. Its crystal structure con.rms that it contains two .1-co-ordinated Fe(CO)4 groups and a 1,3-diphosphaallyl fragment .3 co-ordinated to an Fe(CO)3 moiety. Introduction In recent years there has been a considerable amount of attention paid to the chemistry of organophosphorus cage compounds as they show remarkable similarities to their hydrocarbon cage analogues.1 One di.erence between the two is the ability of organophosphorus cages to act as ligands through P-lone pair donation a feature that has been widely exploited.2 Although not as widely studied as organophosphorus cages cage compounds containing organo-arsenic or -antimony fragments are known and their interaction with transition metal complexes especially in the preparation of Group 15–transition metal cluster compounds has been investigated.3 We have recently added to this area with the synthesis of the mixed P,Sb-substituted cage compound 1 which is prepared in high yield via the oxidative coupling of two equivalents of the diphosphastibolyl ring anion [1,4,2-P2SbC2But 2] with FeCl3.4 Compound 1 o.ers many potential sites for metal fragment co-ordination either through P- or Sb-lone pair donation or .2 co-ordination to its P–C double bonds.Previously we have found that the reaction of 1 with [W(CO)5(THF)] did not lead to the formation of an adduct but to a low yield (9%) of 2 which presumably forms via a metal mediated rearrangement reaction.5 In this earlier study no other product could be isolated from the reaction mixture. We have since discovered that a simple adduct can form from this reaction in addition to those involving [Cr(CO)5(THF)] and [Mo(CO)5(THF)]. We have also investigated the interaction of 1 with [Fe2(CO)9] and other metal carbonyls. The results of these investigations are reported herein. Results and discussion The reaction of compound 1 with 2 equivalents of [M(CO)5- (THF)] M = Cr Mo or W led to the formation of the isostructural 2 1 adducts 3–5 in moderate yields (24 29 and 27% respectively) (Scheme 1). There was no evidence for the formation of higher adducts but a small amount of the previously reported rearrangement product 2 was observed in the preparation of 5.In contrast there was no indication that the chronium or molybdenum analogues of 2 were formed in the preparation of 3 or 4. E.orts to identify the products other than 3–5 from these reactions proved unsuccessful but 31P NMR studies suggested a complex mixture of intractable byproducts that did not contain the unco-ordinated cage 1. Moreover changing the reaction times for the preparations of 3–5 did not signi.cantly e.ect their yields. It is thought that no trace of 5 was seen in the previously reported preparation of 2 because in that case the product mixture was puri.ed by column chromatography (Kieselgel/hexane) and we have found that 5 is not stable to these chromatographic conditions. Interestingly 3 and 4 can be chromatographed but do show signs of partial decomposition when this is attempted.The solution 31P-{1H} NMR spectra of compounds 3–5 are similar and support their proposed structures. In the case of 5 the spectral pattern is consistent with an AMNX spin system and displays four inequivalent phosphorus resonances two at low .eld [P(4) d 346.2 P(1) 268.5] in the normal phosphaalkene region 6 and two at higher .eld [P(3) d 43.6 P(2) 32.0] in the saturated phosphorus region (NB numbering scheme is taken from Fig. 1). All These resonances are close to those seen for the unco-ordinated cage 1 with the exception of that for P(1) which is shifted to higher .eld by ca. 95 ppm which strongly Scheme 1 Reagents and conditions i [W(CO)5(THF)] THF 18 h. 2628 J. Chem. Soc. Dalton Trans. 1999 2627–2631 suggests this is co-ordinated to a W(CO)5 fragment.This is con.rmed by the presence of tungsten satellites (1JWP = 208.0 Hz) about this signal. All the P–P couplings in the spectrum are normal apart from that between P(2) and P(3) (2JPP = 147.5 Hz) which is very large but compares well with the same coupling for 1 (137 Hz). This can perhaps be explained as a through space coupling which results from the short intermolecular P(2)–P(3) distance (see below). The only signi.cant di.erences between the 31P-{1H} NMR spectra of 5 and those of 3 and 4 arises from the position of the P(1) resonance which in the cases of 4 (d 307.7) and 3 (328.5) move closer to the equivalent resonance for the free cage 1 (d 363) as the molecular weight of the metal involved decreases. This phenomenon has been observed and explained on prior occasions for other phosphine–M(CO)5 M = Cr Mo or W adducts.7 The 1H NMR spectra for 3–5 are Fig.1 Molecular structure of compound 5. Table 1 Selected intramolecular distances (Å) and angles () for compound 3 with estimated standard deviations (e.s.d.s) in parentheses Cr(1)–P(1) Sb(1)–C(1) Sb(1)–C(11) Sb(2)–C(11) Sb(2)–P(2) P(2)–C(2) P(3)–C(12) P(4)–C(12) C(1)–C(3) C(11)–C(13) C(1)–Sb(1)–C(11) C(11)–Sb(1)–P(1) C(11)–Sb(2)–P(2) C(11)–Sb(2)–Cr(2) P(2)–Sb(2)–Cr(2) C(2)–P(1)–Sb(1) C(2)–P(2)–C(1) C(1)–P(2)–Sb(2) C(12)–P(3)–Sb(2) C(12)–P(4)–C(11) C(3)–C(1)–P(3) C(3)–C(1)–Sb(1) P(3)–C(1)–Sb(1) C(7)–C(2)–P(2) C(13)–C(11)–P(4) P(4)–C(11)–Sb(2) P(4)–C(11)–Sb(1) C(17)–C(12)–P(4) P(4)–C(12)–P(3) 2.387(3) 2.171(7) 2.236(7) 2.211(9) 2.520(2) 1.790(8) 1.863(8) 1.662(8) 1.606(10) 1.556(10) 89.5(3) 100.3(2) 97.8(2) 137.9(2) 120.59(6) 100.3(3) 108.0(4) 83.1(3) 92.8(2) 104.9(4) 113.8(5) 111.4(5) 112.0(4) 111.7(6) 114.9(6) 107.3(4) 95.5(3) 120.6(6) 124.0(4) Cr(2)–Sb(2) C(12)–C(17) Sb(1)–P(1) Sb(2)–P(3) P(1)–C(2) P(2)–C(1) P(3)–C(1) P(4)–C(11) C(2)–C(7) C(12)–C(17) C(1)–Sb(1)–P(1) C(11)–Sb(2)–P(3) P(3)–Sb(2)–P(2) P(3)–Sb(2)–Cr(2) C(2)–P(1)–Cr(1) Cr(1)–P(1)–Sb(1) C(2)–P(2)–Sb(2) C(12)–P(3)–C(1) C(1)–P(3)–Sb(2) C(3)–C(1)–P(2) P(2)–C(1)–P(3) P(2)–C(1)–Sb(1) C(7)–C(2)–P(1) P(1)–C(2)–P(2) C(13)–C(11)–Sb(2) C(13)–C(11)–Sb(1) Sb(2)–C(11)–Sb(1) C(17)–C(12)–P(3) 2.6290(14) 1.578(10) 2.530(2) 2.500(2) 1.684(8) 1.890(7) 1.925(8) 1.835(8) 1.602(10) 1.589(10) 89.8(2) 84.7(2) 70.11(7) 122.21(6) 141.4(3) 118.01(10) 107.0(3) 108.0(3) 83.0(2) 113.1(5) 98.2(3) 107.5(3) 125.4(6) 122.9(4) 114.7(5) 115.5(5) 107.0(3) 114.9(6) all similar and exhibit four inequivalent tert-butyl resonances that are signi.cantly broadened.This broadening has been attributed to a restricted rotation of these groups due to their proximity to bulky M(CO)5 fragments. Finally the infrared spectra of 3–5 con.rm the presence of ligated M(CO)5 fragments. The molecular structures of compounds 3–5 are isomorphous and so only that for 3 is shown in Fig. 1 though selected bond lengths and angles for all compounds are collected in Tables 1–3. The structures reveal that the framework of the cage starting material has remained intact and that M(CO)5 fragments are co-ordinated in an .1 fashion to P(1) and Sb(2). It is perhaps surprising that one M(CO)5 fragment is preferentially co-ordinated by an Sb instead of one of the three uncoordinated P centres.The reason for this is no doubt steric in Table 2 Selected intramolecular distances (Å) and angles () for compound 4 with e.s.d.s in parentheses Sb(1)–C(1) Sb(1)–P(1) Sb(2)–P(3) Sb(2)–Mo(2) P(1)–C(2) P(2)–C(1) P(4)–C(12) C(1)–C(3) C(11)–C(13) P(3)–C(1) C(1)–Sb(1)–C(11) C(11)–Sb(1)–P(1) C(11)–Sb(2)–P(2) C(11)–Sb(2)–Mo(2) P(2)–Sb(2)–Mo(2) C(2)–P(1)–Sb(1) C(2)–P(2)–C(1) C(1)–P(2)–Sb(2) C(12)–P(3)–Sb(2) C(12)–P(4)–C(11) C(3)–C(1)–Sb(1) P(3)–C(1)–Sb(1) P(4)–C(11)–Sb(1) Sb(1)–C(11)–Sb(2) 2.175(9) 2.534(3) 2.497(2) 2.7593(13) 1.741(12) 1.866(10) 1.683(9) 1.603(12) 1.583(11) 1.946(10) 88.9(3) 100.0(3) 97.0(3) 139.2(2) 120.27(7) 103.0(4) 111.7(5) 83.1(3) 92.6(3) 104.8(5) 110.9(6) 113.2(4) 97.0(4) 108.0(4) Sb(1)–C(11) Sb(2)–C(11) Sb(2)–P(2) Mo(1)–P(1) P(2)–C(2) P(3)–C(12) P(4)–C(11) C(2)–C(7) C(12)–C(17) C(1)–Sb(1)–P(1) C(11)–Sb(2)–P(3) P(3)–Sb(2)–P(2) P(3)–Sb(2)–Mo(2) C(2)–P(1)–Mo(1) Mo(1)–P(1)–Sb(1) C(2)–P(2)–Sb(2) C(12)–P(3)–C(1) C(1)–P(3)–Sb(2) P(2)–C(1)–P(3) P(2)–C(1)–Sb(1) P(1)–C(2)–P(2) P(4)–C(11)–Sb(2) P(4)–C(12)–P(3) 2.203(9) 2.211(9) 2.517(3) 2.527(3) 1.847(10) 1.893(10) 1.829(10) 1.426(14) 1.511(13) 89.9(3) 85.2(2) 69.86(9) 121.20(7) 140.4(4) 116.49(12) 106.5(3) 106.4(4) 82.1(3) 97.7(4) 107.8(4) 116.6(6) 107.1(4) 123.2(6) Table 3 Selected intramolecular distances (Å) and angles () for compound 5 with e.s.d.s in parentheses W(1)–P(1) Sb(1)–C(1) Sb(1)–P(1) Sb(2)–P(3) P(1)–C(2) P(2)–C(1) P(3)–C(1) P(4)–C(11) C(2)–C(7) C(12)–C(17) C(1)–Sb(1)–C(11) C(11)–Sb(1)–P(1) C(11)–Sb(2)–P(2) C(11)–Sb(2)–W(2) P(2)–Sb(2)–W(2) C(2)–P(1)–Sb(1) C(2)–P(2)–C(1) C(1)–P(2)–Sb(2) C(12)–P(3)–Sb(2) C(12)–P(4)–C(11) C(3)–C(1)–P(3) C(3)–C(1)–Sb(1) P(3)–C(1)–Sb(1) C(7)–C(2)–P(2) C(13)–C(11)–P(4) P(4)–C(11)–Sb(2) P(4)–C(11)–Sb(1) C(17)–C(12)–P(4) P(4)–C(12)–P(3) 2.513(3) 2.196(10) 2.521(3) 2.499(3) 1.683(11) 1.873(11) 1.906(10) 1.848(11) 1.54(2) 1.523(14) 88.9(4) 99.9(3) 97.4(3) 138.3(3) 120.30(7) 101.6(4) 109.4(5) 83.2(3) 93.8(3) 104.6(5) 114.3(7) 111.0(7) 111.6(5) 112.8(8) 112.3(7) 107.2(5) 95.8(4) 118.9(8) 122.6(6) W(2)–Sb(2) Sb(1)–C(11) Sb(2)–C(11) Sb(2)–P(2) P(2)–C(2) P(3)–C(12) P(4)–C(12) C(1)–C(3) C(11)–C(13) C(1)–Sb(1)–P(1) C(11)–Sb(2)–P(3) P(3)–Sb(2)–P(2) P(3)–Sb(2)–W(2) C(2)–P(1)–W(1) W(1)–P(1)–Sb(1) C(2)–P(2)–Sb(2) C(12)–P(3)–C(1) C(1)–P(3)–Sb(2) C(3)–C(1)–P(2) P(2)–C(1)–P(3) P(2)–C(1)–Sb(1) C(7)–C(2)–P(1) P(1)–C(2)–P(2) C(13)–C(11)–Sb(2) C(13)–C(11)–Sb(1) Sb(2)–C(11)–Sb(1) C(17)–C(12)–P(3) 2.7586(9) 2.218(10) 2.202(10) 2.509(3) 1.815(10) 1.843(11) 1.702(11) 1.597(14) 1.561(14) 89.7(3) 84.5(3) 70.13(10) 122.75(7) 140.8(4) 117.44(12) 107.0(3) 109.6(5) 82.8(3) 113.2(7) 99.1(5) 107.0(5) 126.2(8) 121.0(6) 115.1(7) 116.7(7) 107.8(4) 117.9(8) J.Chem. Soc. Dalton Trans. 1999 2627.2631 2629 origin as P(2) P(3) and P(4) are bonded on either side to two bulky CBut fragments. The P(1).M(1) distances in 3.5 all lie in the normal regions as do the Sb(2).M(2) bond lengths {cf. 2.625 A in [Sb2Ph4{Cr(CO)5}2];8 2.756 A in [Mo(CO)5(SbPh3)] and 2.754 A in [W(CO)5(SbPh3)] 9}. All bond lengths within the framework of the cage ligands in 3.5 are consistent with single bonded interactions except those for P(1).C(2) and P(4).C(12) which are typical for localized P.C double bonds.As in 1 complexes 3.5 contain very strained diphosphastibacyclobutane fragments Sb(2)P(3)C(1)P(2) in which the cross ring P P distances (3 2.883 4 2.871 5 2.877; cf. 2.822 A in 1) are well within the sum of the van der Waals radii 3.8 A for two phosphorus atoms. These close contacts could explain the large two bond PP couplings between P(2) and P(3) in the 31P-{1H} NMR spectra of these complexes. The reactions of compound 1 with a number of other transition metal carbonyl complexes e.g. [Co2(CO)8] were investigated but this generally led to decomposition of the cage compound to an intractable mixture of products. However some success was achieved with the reaction of 1 with four equivalents of [Fe2(CO)9] in hexane at room temperature.This led to the isolation of 6 in moderate yield (33%) after column chromatography (Kieselgel hexane.diethyl ether 10 1) (Scheme 2). Compound 6 is a red crystalline solid that is thermally stable in the solid state (decomp. 160 C) but slowly decomposes in solution over 3 d. It seems likely that the formation of compound 6 proceeds via the initial formation of a 3 :1 adduct 7 though no evidence for such a complex was seen in the NMR spectra of the product mixture even if the reaction was stopped after one hour. If this is the case 7 could rearrange via the insertion of an iron carbonyl fragment into the Sb(2).P(3) bond (see Fig. 2) to give 6 with a concomitant loss of one carbonyl ligand. Similar insertions of transition metal carbonyl fragments into Group 15.Group 15 bonds have been reported in the formation of Group 15.transition metal clusters.3a,b The iron centre in the Fe(CO)3 fragment of 6 is best described as being ¥ò bonded to an antimonide fragment and ¥ç3 bonded to a 1,3-diphosphaallyl system. It is noteworthy that 1,3-diphosphaallyl complexes have been previously reported 10 and in particular those involving ¥ç3 co-ordination to a Fe(CO)3 unit are known.11 It is also interesting that the cage rearrangement that led to the formation of 2 Scheme 2 Reagents and conditions i [Fe2(CO)9] hexane 18 h; ii CO. Sb P P P Sb P But But But But (OC)4Fe (OC)4Fe Fe(CO)4 Sb P P P Sb P But But But But (OC)4Fe (OC)4Fe Fe(CO)3 1 i 6 7 ii was thought to occur via cleavage of the other Sb.P bond in the strained four-membered SbPCP ring in the cage ligand.5 The spectroscopic data for compound 6 support its proposed structure.Its 31P-{1H} NMR spectrum displays a signal at low .eld (¥ä 300.5) which has been assigned to the phosphorus centre involved in the localized P(1).C(2) double bond. The signals for P(3) and P(4) (¥ä 107.3 and 122.4) are in the normal region for ¥ç3 co-ordinated 1,3-diphosphaallyl systems though the 2JP(3)P(4) coupling of 10 Hz is low for such systems. Also unusual is the relatively low .eld resonance for the saturated phosphorus centre P(2) at ¥ä 94.4 which can be compared to a value of ¥ä 18.6 for the same phosphorus in the cage 1,4 prior to rearrangement. As expected the 1H NMR spectrum of 6 exhibits four broad singlets for the four inequivalent rotationally hindered tert-butyl groups.Compound 6 crystallizes with two crystallographically independent molecules in the asymmetric unit that are geometrically very similar. As a result the molecular structure of only one of these is depicted in Fig. 2 (see also Table 4) and con.rms that the cage framework of the starting material has rearranged to include one Fe(CO)3 fragment within the cage structure and two ¥ç1-ligated Fe(CO)4 fragments. The P(1).Fe(3) and Sb(2).Fe(2) distances [2.213(6) and 2.546(3) A respectively] are in the normal region for such interactions {cf. 2.239 A in [Fe(CO)4(PPh2H)] 12 and 2.547 A in [Fe(CO)4(SbBut 3)] 13}. The iron.antimonide bond length Sb(2).Fe(1) 2.642(3) A is considerably longer than the Sb(2).Fe(2) interaction but still in the typical range.The P(1).C(2) bond length 1.70(2) A is also in the normal range for localized P.C double bonds. An inspection of the P(3).C(12).P(4) allyl fragment reveals that it is ¥ç3 co-ordinated to the Fe(CO)3 fragment [Fe(1).P(4).C(12) 61.9(6) Fe(1).P(3).C(12) 62.2(5)] but in a rather unsymmetrical fashion with signi.cant di.erences in the P(3).Fe(1) [2.370(6) A] and P(4).Fe(1) [2.443(5) A] bond lengths. These combined with the iron.allyl carbon bond length [Fe(1).C(12) 2.23(2) A] are longer than in similar systems e.g. [Fe(CO)3- {¥ç3-Mes*PC(H)PMes*[Ni(¥ç5-C5H5)]}] (Mes* = C6H2But 3-2,4,6) Table 4 Selected intramolecular distances (A) and angles () for compound 6 with e.s.d.s in parentheses Sb(1).C(1) Sb(1).P(1) Sb(2).P(2) Sb(2).Fe(1) Fe(1).P(4) P(1).C(2) P(2).C(2) P(3).C(1) P(4).C(11) C(1).Sb(1).C(11) C(11).Sb(1).P(1) C(11).Sb(2).Fe(2) C(11).Sb(2).Fe(1) Fe(2).Sb(2).Fe(1) C(22).Fe(1).P(3) C(12).Fe(1).P(3) C(22).Fe(1).P(4) C(12).Fe(1).P(4) C(22).Fe(1).Sb(2) C(12).Fe(1).Sb(2) P(4).Fe(1).Sb(2) C(2).P(1).Sb(1) C(1).P(2).C(2) C(2).P(2).Sb(2) C(12).P(3).Fe(1) C(12).P(4).C(11) C(11).P(4).Fe(1) P(2).C(1).Sb(1) P(1).C(2).P(2) P(4).C(11).Sb(1) P(4).C(12).P(3) P(3).C(12).Fe(1) 2.23(2) 2.554(5) 2.529(5) 2.642(3) 2.443(5) 1.70(2) 1.89(2) 1.92(2) 1.88(2) 94.8(6) 96.9(4) 126.9(4) 87.6(5) 122.25(11) 93.6(7) 47.4(4) 116.2(6) 42.6(4) 170.9(6) 97.2(5) 72.7(2) 105.1(7) 106.5(8) 100.4(5) 62.2(5) 112.4(8) 101.4(5) 107.8(7) 116.6(10) 104.6(7) 125.8(10) 70.4(5) Sb(1).C(11) Sb(2).C(11) Sb(2).Fe(2) Fe(1).P(3) Fe(3).P(1) P(2).C(1) P(3).C(12) P(4).C(12) C(1).Sb(1).P(1) C(11).Sb(2).P(2) P(2).Sb(2).Fe(2) P(2).Sb(2).Fe(1) C(23).Fe(1).P(3) C(21).Fe(1).P(3) C(23).Fe(1).P(4) C(21).Fe(1).P(4) P(3).Fe(1).P(4) C(21).Fe(1).Sb(2) P(3).P(1).Sb(2) C(2).P(1).Fe(3) Fe(3).P(1).Sb(1) C(1).P(2).Sb(2) C(12).P(3).C(1) C(1).P(3).Fe(1) C(12).P(4).Fe(1) P(2).C(1).P(3) P(3).C(1).Sb(1) P(4).C(11).Sb(2) Sb(2).C(11).Sb(1) P(4).C(12).Fe(1) 2.28(2) 2.19(2) 2.546(3) 2.370(6) 2.213(6) 1.85(2) 1.85(2) 1.71(2) 86.1(5) 99.7(5) 117.63(13) 95.05(14) 91.9(6) 167.7(6) 153.7(6) 85.6(6) 82.4(6) 89.5(6) 89.6(2) 134.5(7) 119.3(2) 95.3(5) 110.1(7) 114.4(5) 61.9(6) 109.8(9) 108.7(7) 95.4(8) 107.1(6) 75.5(6) 2630 J.Chem. Soc. Dalton Trans. 1999 2627–2631 [P–Fe 2.309 average Fe–C (allyl) 2.025(7) Å11]. In addition there appears to be little delocalization over the P(3)–C(12)– P(4) fragment in 6 with the bond lengths P(3)–C(12) [1.85(2) Å] and P(4)–C(12) [1.71(2) Å] being close to what would be expected for single and double P–C bonds respectively.However the inaccuracy in these bond lengths makes it di.cult to be certain of the degree of delocalization in this system. The unsymmetrical nature of the bonding in the co-ordinated diphosphaallylic fragment can perhaps be explained by the strain present in that part of the molecule which forces the C(1) and C(11) atoms considerably out of the plane of the PCP unit. Moreover the low 2JP(3)P(4) coupling observed in the 31P-{1H} NMR spectrum of 6 is consistent with with the lone pairs of P(3) and P(4) being constrained to the exo positions of the diphosphaallyl fragment by the nature of the cage framework. Conclusion This study highlights the versatility of the antimony containing cage compound 1 as a ligand in the formation of transition metal carbonyl adducts 3–5.In addition the presence of relatively weak and strained Sb–P bonds within 1 can allow its rearrangement via Sb–P bond cleavage upon metal coordination to a.ord the novel iron containing cage compound 6. Experimental General remarks All manipulations were carried out using standard Schlenk and glove-box techniques under an atmosphere of high purity argon or dinitrogen. The solvents tetrahydrofuran (THF) and hexane were distilled over Na/K alloy then freeze/thaw degassed prior to use. Dichloromethane was distilled from CaH2 prior to use. The 1H 13C and 31P NMR spectra were recorded on either a Bruker WM-250 or AM 400 spectrometer in C6D6 and referenced to the residual 1H resonances of the solvent used (1H) or to external 85% H3PO4 d 0.0 (31P).FAB Mass spectra were recorded using a VG-autospec instrument (Cs ions 25 kV 3-nitrobenzyl alcohol matrix). Melting points were determined in sealed glass capillaries under argon and are uncorrected. Reproducible elemental analyses of all compounds could not be obtained due to their slight light sensitivity. However NMR data of freshly puri.ed samples suggested high purity of the bulk materials. The starting materials [M(CO)5(THF)] (M = Cr Mo or W) were generated by UV irradiation of THF solutions of [M(CO)6] for 8 h at ambient temperature and used in solution without further puri.cation. Compound 1 was prepared Fig. 2 Molecular structure of compound 6 (tert-butyl groups omitted for clarity). by a published procedure.4 All other reagents were used as received.Syntheses [{Cr(CO)5}2(1 :1-P4Sb2C4But 4)] 3. A solution of compound 1 (0.125 g 0.19 mmol) in THF (10ml) was added to a solution of [Cr(CO)5(THF)] (0.11 g 0.5 mmol) in THF (75 ml) at ambient temperature and stirred for 18 h. Volatiles were removed in vacuo and the residue was extracted with hexane. Puri.cation by column chromatography (Kieselgel hexane) and recrystallization from diethyl ether a.orded 3 as red crystals (0.05 g 24%) mp 170 C. 1H NMR (250 MHz C6D6 298 K) d 1.13 (br) 1.30 (br) 1.52 (br) and 1.55 (br) (4 × 9 H But). 31P-{1H} NMR (101.2 MHz C6D6 298 K) d 16.0 [dd P(2) 2J(P1P2) = 25 2J(P2P3) = 148] 31.2 [dd P(3) 2J(P3P4) = 24 2J(P2P3) = 148] 328.5 [d P(1) 2J(P1P2) = 25] and 355.4 [d P(4) 2J(P3P4) = 24 Hz].IR (Nujol) .� /cm1 2058.1s 1960.4w 1946.2s and 1927.7s. FAB mass spectrum m/z 888 ([M 5 CO] 9) 748 ([M 10 CO] 17) 696 ([M 5 CO Cr(CO)5] 100) and 644 ([M 2 Cr(CO)5] 33%). [{Mo(CO)5}2(1 :1-P4Sb2C4But 4)] 4. A solution of compound 1 (0.125 g 0.19 mmol) in THF (10 ml) was added to a solution of [Mo(CO)5(THF)] (0.13 g 0.5 mmol) in THF (75 ml) at ambient temperature and stirred for 18 h. Volatiles were removed in vacuo and the residue was extracted with hexane. Puri.cation by column chromatography (Kieselgel hexane) and recrystallization from diethyl ether a.orded 4 as red crystals (0.06 g 29%) mp 159 C (decomp.). 1H NMR (250 MHz C6D6 298 K) d 1.14 (br) 1.30 (br) 1.55 (br) and 1.61 (br) (4 × 9 H But). 31P-{1H} NMR (101.2 MHz C6D6 298 K) d 30.4 [dd P(2) 2J(P1P2) = 23 2J(P2P3) = 147] 43.0 [dd P(3) 2J(P3P4) = 27 2J(P2P3) = 147] 307.7 [d P(1) 2J(P1P2) = 23] and 346.3 [d P(4) 2J(P3P4) = 27].IR (Nujol) .� /cm1 2070m 1948.5s and 1929.1s. FAB mass spectrum m/z 1115 (M 5) 881([M H Mo(CO)5] 13) and 644 ([M H 2 Mo(CO)5] 100%). [{W(CO)5}2(1 :1-P4Sb2C4But 4)] 5. A solution of compound 1 (0.15 g 0.23 mmol) in THF (10 ml) was added to a solution of [W(CO)5(THF)] (0.23 g 0.58 mmol) in THF (75 ml) at ambient temperature and stirred for 18 h. Volatiles were removed in vacuo and the residue was extracted with diethyl ether. Recrystallization from dichloromethane a.orded 5 as red crystals (0.08 g 27%) mp 175 C (decomp.). 1H NMR (250 MHz C6D6 298 K) d 1.28 (br) 1.33 (br) 1.35 (br) and 1.36 (br) (4 × 9 H But). 31P-{1H} NMR (101.2 MHz C6D6 298 K) d 32.0 [dd P(2) 2J(P1P2) = 22 2J(P2P3) = 148] 43.6 [dd P(3) 2J(P3P4) = 23 2J(P3P2) = 148] 268.5 [d P(1) 2J(P1P2) = 22 1JWP = 208] and 346.2 [d P(4) 2J(P4P3) = 23 Hz].IR (Nujol) .� /cm1 2068.0m 1940.7s and 1932.2m. FAB mass spectrum m/z 1293 ([M H] 10) 969 ([M H W(CO)5] 25) and 644 ([M H 2 W(CO)5] 100%). [{Fe(CO)4}2{Fe(CO)3(3 :1-P4Sb2C4But 4)}] 6. To a solution of compound 1 (0.125 g 0.19 mmol) in hexane (30 ml) at ambient temperature was added [Fe2(CO)9] (0.27 g 0.475 mmol) and the resulting solution stirred for 18 h. Volatiles werved in vacuo and the residue was extracted with hexane. Puri.cation by column chromatography (Kieselgel hexane–diethyl ether 10 1) and recrystallization from hexane a.orded 6 as red crystals (0.06 mg 33%) mp 160 C. 1H NMR (250 MHz C6D6 278 K) d 1.12 (br) 1.20 (br) 1.29 (br) and 1.48 (br) (4 × 9 H But ).31P-{1H} NMR (101.2 MHz C6D6 298 K) d 94.4 [dd P(2) 2J(P2P1) = 40 2J(P2P3) = 41] 107.3 [d P(4) 2J(P4P3) = 10] 122.4 [dd P(3) 2J(P3P4) = 10 2J(P3P2) = 40] and 300.5 [d P(1) 2J(P1P2) = 40 Hz]. IR (Nujol) .� /cm1 2036.0s 1984.8m and 1953.6m. FAB mass spectrum m/z 1119 (M 5) 979 ([M Fe(CO)3] 7) 812 ([M Fe2(CO)7] 37) and 765 ([M Fe2(CO)9] 100%). J. Chem. Soc. Dalton Trans. 1999 2627.2631 2631 Table 5 Crystal data for [{M(CO)5}2(¥ç1 :¥ç1-P4Sb2C4But 4)] (M = Cr 3 Mo 4 or W 5) and [{Fe(CO)4}2{Fe(CO)4}2{Fe(CO)3(¥ì3 :¥ç1-P4Sb2C4But 4)}] 6 3 4 5 6 Chemical formula M Crystal system Space group a/A b/A c/A ¥â/ V/A3 ZT /K ¥ì(Mo-K¥á)/cm1 Re.ections collected No. unique re.ections R (all data) [I > 2¥ò(I)] R (all data) [I > 2¥ò(I)] C30H36Cr2O10P4Sb2 1027.97 Monoclinic P21/n 10.2670(10) 22.2630(10) 16.997(2) 93.060(12) 3879.5(6) 4 150(2) 21.38 14993 5745 0.0866 0.0389 0.0797 0.0723 C30H36Mo2O10P4Sb2 1115.85 Monoclinic P21/n 10.324(3) 22.469(2) 17.2510(10) 93.070(10) 3996.0(12) 4 150(2) 21.59 14464 5564 0.0893 0.0378 0.0842 0.0765 C30H36W2O10P4Sb2 1291.67 Monoclinic P21/n 10.314(2) 22.394(5) 17.1990(10) 93.07(2) 3966.8(12) 4 150.(2) 73.38 15179 5757 0.0695 0.0336 0.0690 0.0633 C31H36Fe3O11P4Sb2 1119.53 Monoclinic P21/n 20.047(2) 18.059(10) 22.781(6) 92.420(10) 8240(5) 8 150(2) 25.33 26338 11069 0.1758 0.0526 0.1152 0.0903 Structure determinations Crystals of compounds 3.6 suitable for structure determination were mounted in silicone oil.Intensity data were measured on a FAST14 area detector di.ractometer using Mo-K¥á radiation.The structures of 4 and 5 were solved by direct methods and those of 3 and 6 by the heavy atom method (SHELXS 8615) and re.ned by least squares using the SHELXL 93 16 program. The structures were re.ned on F 2 using all data. Neutral-atom complex scattering factors were employed.17 Empirical absorption corrections were carried out by the DIFABS method.18 Crystal data details of data collections and re.nement are given in Table 5. Anisotropic thermal parameters were re.ned for all non-hydrogen atoms. The hydrogen atoms in all structures were included in calculated positions (riding model). CCDC reference number 186/1533. Acknowledgements We gratefully acknowledge .nancial support from EPSRC (studentship for R. C. T.). References 1 K.B. Dillon F. Mathey and J. F. Nixon in Phosphorus The Carbon Copy Wiley Chichester 1998 R. Streubel Angew. Chem. Int. Ed. Engl. 1995 34 436; A. Mack and M. Regitz Chem. Ber. 1997 130 823 and refs. therein; G. Fritz Adv. Inorg. Chem. 1987 31 171 and refs. therein. 2 P. B. Hitchcock C. Jones and J. F. Nixon J. Chem. Soc. Chem. Commun. 1995 2167; V. Caliman P. B. Hitchcock C. Jones and J. F. Nixon Phosphorus Sulfur Silicon Relat. Elem. 1996 113 15. 3 (a) K. H. Whitmire Adv. Organomet. Chem. 1997 42 1; (b) K. H. Whitmire in Chemistry of Arsenic Antimony and Bismuth ed. N. C. Norman Blackie Academic London 1998; (c) A. J. Dimaio and A. L. Rheingold Chem. Rev. 1990 90 169; (d ) S. P. Mattawana K. Promrai J. C. Fettinger and B. W. Eichhorn Inorg. Chem. 1998 37 6222 and refs. therein. 4 S.J. Black M. D. Francis and C. Jones Chem. Commun. 1997 305. 5 S. J. Black D. E. Hibbs M. B. Hursthouse C. Jones K. M. A. Malik and R. C. Thomas J. Chem. Soc. Dalton Trans. 1997 4321. 6 K. Karaghioso. in Multiple Bonds and Low Co-ordination in Phosphorus Chemistry eds. M. Regitz and O. J. Scherer G. Thieme Stuttgart 1990 pp. 463.465. 7 C. Elschenbroich S. Voss O. Schiemann A. Lippek and K. Harms Organometallics 1998 17 4417. 8 J. von Seyerl and G. Huttner Cryst. Struct. Commun. 1980 9 1099. 9 M. J. Aroney I. E. Buys M. S. Davies and T. W. Hambley J. Chem. Soc. Dalton Trans. 1994 2827. 10 R. El-Ouatib D. B. Tkatchenko G. E. Moghadam and M. Koenig J. Organomet. Chem. 1993 453 77; R. Appel W. Schuhn and F. Knoch J. Organomet. Chem. 1987 319 345. 11 H. Schmidbaur W. Graf and G. Muller Angew. Chem. Int. Ed. Engl. 1988 27 417. 12 B. T. Kilbourn V. A. Raeburn and D. T. Thompson J. Chem. Soc. A 1969 1906. 13 A. L. Rheingold and M. E. Fountain Acta Crystallogr. Sect. C 1985 41 1162. 14 J. A. Darr S. A. Drake M. B. Hursthouse and K. M. A. Malik Inorg. Chem. 1993 32 5704. 15 G. M. Sheldrick Acta Crystallogr. Sect. A 1990,46 467. 16 G. M. Sheldrick SHELXL 93 Program for Crystal Structure Re.nement University of Gottingen 1993. 17 International Tables for X-Ray Crystallography eds. J. A. Ibers and W. C. Hamilton Kynoch Press Birmingham 1974 vol. 4. 18 N. P. C. Walker and D. Stuart Acta Crystallogr. Sect. A 1983 39 158; adapted for FAST geometry by A. I. Karavlov University of Wales Cardi. 1991. Paper 9/0313

ISSN:1477-9226    

DOI:10.1039/a903136g

出版商:RSC    

年代:1999

数据来源: RSC