摘要:

Photochemical Reactions of Transition Metal Organyl Complexes with Olefines, 31). – [4 + 5] Cycloaddition of Conjugated Dienes to Tricarbonyl(η5‐2,4‐dimethyl‐2,4‐pentadienyl)manganeseTricarbonyl(η5‐2,4‐dimethyl‐2,4‐pentadienyl)manganese [1] reacts photochemically with the acyclic conjugated dienes 1,3‐butadiene [A], 2‐methyl‐1,3‐butadiene [B], (E)‐1,3‐pentadiene (C), (E,E)‐2,4‐hexadiene (D), 2,4‐dimethyl‐1,3‐pentadiene (E), 2,4‐hexadien‐1‐ol (F), and methyl 2,4‐hexadienoate (G) in a formal [4 + 5] cycloaddition to give tricarbonylmanganese complexes with η3:2‐2,6‐cyclononadien‐1‐yl ligands (2A‐2G). In addition, the reaction of1withAyields thermolabile [η3:2:2‐1‐(3‐butene‐1,2‐diyl)‐1,3‐dimethyl‐2,6‐cyclononadiene]dicarbonylmanganese (3A) andE,EandE,Zisomers of [η3‐1‐(2‐butene‐1,1‐diyl)‐1,3‐dimethyl‐2,6‐cyclononadiene]tetracarbonylmanganese (4A, 4A] as byproducts. Similarly,1reacts withBto form tetracarbonyl[η3‐1‐(3‐methyl‐2‐butene‐1,1‐diyl)‐1,3,6‐trimethyl1‐2,6‐cyclononadiene]manganese (4B) in a side reaction. The crystal and molecular structures of tricarbonyl(η3:2‐1,3,5,5,7‐pentamethyl‐2,6‐cyclononadien‐1‐yl]manganese (2E) and of3Aare determined by X‐ray structure analyses. In each of the f

ISSN:0009-2940    

DOI:10.1002/cber.19911240102

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

Synthesis and Structure of Bis[bis(diisopropylamino)phosphino]chalcogenidesPhosphorodiamidous chalcogeno‐anhydrides [(R2N)2P]2X (R = Me2CH; X = S, Se, Te) (2a‐c) have been obtained by insertion of elemental sulfur, selenium, or tellurium into the P–P bond of the corresponding diphosphane (1). The structure of2aand2chas been confirmed by an X‐ray diff

ISSN:0009-2940    

DOI:10.1002/cber.19911240103

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

Derivatives of Borole, XVI1),—Bis(borole)nickel Complexes2)The dilithium 1‐(dialkylamino)dihydroborolediides Li2[C4H4‐BNR2]2a, b: R = Me, Et) react with NiCl2· DME to give bis(borole)nickel complexes Ni(C4H4BNR2)2. Nucleophilic substitution reactions are used to produce a large variety of derivatives Ni(C4H4BR)21(e.g. R = H,tBu, F, Cl, Br, I, OH, OMe). Treatment of Ni(C4H4BCl)2(tg) with LiO(CH2)3OLi in THF produces a polymer and a dinuclear complex (μ‐{η5:η5‐[(CH2)3(OBC4H4)2]}2Ni2(3) which crystallizes from CH2Cl2as solvate3· CH2Cl2. The complexes1gand3· CH2Cl2are characterized by X‐ray diffraction work. Barriers to internal ring‐ring rotation are measured by variable‐temperature NMR spectroscopy. The B—H bond of Ni(C4H4BH)2(1a) is remarkably inert and does not react with H2O or with carboxylic acids in THF at room temperature. With PhCHO slow formation of the benzyloxy compound Ni(C4H4BOCH2Ph)2(1 m) is observed at 100°C. For typical complexes such as the phenyl derivative1ecyclic voltammetry in CH2Cl2reveals an irreversible oxidation at 1.32 and a quasi‐reversible re

ISSN:0009-2940    

DOI:10.1002/cber.19911240104

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

Derivatives of Borole, XVII1). – {η5‐[1‐(Diisopropylamino)borole]}metal Complexes: Syntheses, Protonation, Internal RotationNew complexes M(CO)4L (M = Cr, W),cis‐M(CO)2L2[M = Mo, W (not isolated)], and (COD)NiL have been prepared from the Diels‐Alder dimer L2, where L is 1‐(diisopropylamino)borole, C4H4BNiPr2. Complexes of L can be protonated at the nitrogen atom to give stable salts such as [Cr(CO)4(LH)]BF4, [Fe(CO)3(LH)]BF4, [(C6Me6)Ru(LH)]BF4, and [CpCo(LH)]BF4; B — N bond dissociation is not observed. Barriers to internal rotation have been determined by variable temperature NMR spectroscopy for Cr(CO)4L, (COD)NiL, and NiL2. Three processes have been identified: rotation of the NiPr2group around the B — N bond, gear‐mesh rotation of the isopropyl groups around the C — N bonds, and rotation of L with respect to

ISSN:0009-2940    

DOI:10.1002/cber.19911240105

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

(Perfluoroalkyl)(dimethylamino)sulfonium HexafluoroarsenatesMeN = S(CF3)2(5) is alkylated by Me3O⊕AsF⊖6to Me2N‐S(CF3)⊕2AsF⊖6(4). From5and MeOSO⊕AsF⊖6(6) MeOS(O)‐N(Me)S(CF3)⊕2AsF⊖6(7) is formed as a relatively stable primary product. Decomposition of7gives the expected4only in poor yield. Nucleophilic substitution of the sulfur‐bonded fluorine in CF3SF⊕2AsF⊖6(8) by Me3SiNMe2yields CF3S(NMe2)⊕2AsF⊖6(9). Similarly, (CF3)2CFSF⊕2AsF⊖6(10) reacts with dimethyl(trimethylsilyl)amine to give (CF3)2CFS(NMe2)⊕2AsF⊖6(11). The structures of4and9are elucidated by X‐ray analyses, and the influence of the s

ISSN:0009-2940    

DOI:10.1002/cber.19911240106

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

Addition of Alkenes to 5‐(Trifluoromethyl)‐1,3,2,4,6‐dithiatriazinesDechlorination of 1,3‐dichloro‐5‐(trifluoromethyl)‐1,3,2,4,6‐dithiatriazine (1) with Ph3Sb gives (CF3CN3S2)n(2) in quantitative yield. By 1,3‐addition of alkenes (dicyclopentadiene, cyclopentene,cis‐ andtrans‐2‐butene, propene, and ethene) to2the corresponding penta‐ (4a), tri‐(5a), and bicyclic ring systems6a, 6b, 7, 8a, 8b, and9are prepared in 65–85% yields. The molecular structures of6aand7were determined by single‐crystal X‐ray analysis; the other structures were derived from NMR data. The NMR analyses are in accordance with MNDO calculations. For4aand5aonly the thermodynamically favouredanti‐isomers are found, as expected from these calculations; for6and8they show satisfactory agreement foranti/syn‐proportions as determined by NMR spectroscopy. The product distribution corresponds to a symmetry‐allowed alke

ISSN:0009-2940    

DOI:10.1002/cber.19911240107

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

Synthesis and Properties of 1,2,4,3‐Thiadiazaboretidines. Crystal Structure of 2,4‐Di‐tert‐butyl‐3‐phenyl‐1,2,4,3‐thiadiazaboretidineReaction of sulfur diimides with alkyl(aryl)bis(methylthio)boranes leads to reductive 1,3‐cycloaddition of the NSN sequence with formation of the 1,2,4,3‐thiadiazaboretidines2a‐g. NMR (1H,11B,13C,15N,29Si), mass spectra and the results of the X‐ray analysis of21are reported and discussed. The11B chemical shifts have been calculated for 3‐phenyl‐1,2,4,3‐thiadiazaboretidine and some related model compounds by the IGLO method and correlate acceptably

ISSN:0009-2940    

DOI:10.1002/cber.19911240108

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

Preparation of (Perfluoroalkyl)halogeno‐1,3‐diselenetanes from the Corresponding Selenocarbonyl Fluorides and Reactions with Boron Trichloride or Arsenic Pentafluoride1)Reactions of Hg(SeRt)2(Rt= C2F5, C3F7, CF3) with (C2H5)2All or All3in octamethylcyclotetrasiloxane produce the unstable perfluoroalkaneselenocarbonyl fluorides1[R1= CF3(1 a), C2F5(1 b), CF3Se (1 c)]. These compounds are very reactive and polymerize to rubberlike products. On heating the polymers decompose almost quantitatively to the monomers or dimers. In CFCl3solution1dimerizes at 20°C in sunlight to the correspondingcis/trans‐1,3‐diselenetanes2. The structure of2 bis determined by single crystal X‐ray diffraction. Different selenocarbonyl derivatives add to unsymmetrically substituted 1,3‐diselenetanes3.1 aand1 breact with cyclopentadiene to form the [4 + 2] cycloaddition products4aand4c. Halogen exchange reactions take place between2a—dand BCl3. Thecis‐isomers react much faster than thetrans‐isomers to give a mixture ofcis‐,trans‐forms of5. When2c,dis treated with BCl3it is possible to isolate and characterize the puretrans‐isomer2d, which is separated by preparative gas chromatography from5c,d. Fluorine abstraction with formation of 1,3‐diselenetan‐2‐ylium ions (6a—f) are accomplished by

ISSN:0009-2940    

DOI:10.1002/cber.19911240109

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

Transition‐Metal Silyl Complexes, 361). — On the Question of Gold‐Gold Interactions in Ph2P[CH2]t(2)PPh2‐Bridged Dinuclear Gold Silyl ComplexesDinuclear silyl gold complexes of the type dppm(AuSiR3)2(1) or dppe(AuSiR3)2(2) are prepared by the reaction of dppm‐(AuCl)2or dppe(AuCl)2with two equivalents of LiSi(aryl)3or LiSi(SiMe3)3The complex dppe[AuSi(SiMe3)3]2(2 c) exhibits crystallographic inversion symmetry, and therefore the distance between both gold atoms is a maximum. In dppm‐(AuSiPh3)2(1b) a gold‐gold interaction between both gold atoms is observed [Au — A

ISSN:0009-2940    

DOI:10.1002/cber.19911240110

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY

摘要:

Contributions to the Chemistry of Phosphorus, 2101.2). – Pentaorganyltricyclononaphosphanes with a Structure Analogous to Brexane,b‐P9R5(R = Me, Et,iPr)The reaction of RPCl2, P4, and magnesium provides two constitutionally isomeric pentaorganyltricyclononaphosphanes. Besides the isomer with a P9skeleton analogous to that of noradamantane (a‐P9R5), which was already identified, a further isomer of lower relative abundance (b‐P9R5) has now been found. In the case of R = Et (2) it has been isolated as a pale yellow, oily liquid and, in the cases of R = Me (1) andiPr (3), has been highly enriched. According to their31P{1H}‐NMR spectra,1—3have a constitution analogous to that of the hydrocarbon brexane, thus being 2,4,5,8,9‐pentaorganyltricyclo[4.3.0.03.7]nonaphosphanes. They are each formed as mixtures of several configurational isomers, which differ in their relative arrangements of the o

ISSN:0009-2940    

DOI:10.1002/cber.19911240111

出版商:WILEY‐VCH Verlag    

年代:1991

数据来源: WILEY