摘要:

1980 23 Aromatic Sulphonation. Part 742 Sulphonation of Some 9-Alkenyl- anthracenes and the Corresponding Benzenes with Dioxan-SO3 By Freek van de Griendt and Hans Cerfontain,' Laboratory for Organic Chemistry, University of Amsterdam, Nieuwe Achtergracht 129, 101 8 WS Amsterdam, The Netherlands The sulphonation of six alkenylarenes with dioxan-SO, in dioxan has been studied at 17 "C. With the substrates 9-vinyl- (3a), 9-(prop-2-enyl)- (3b), and 9-[(E)-but-2-enyl]-anthracene (3c), and (€)-prop-1 -and -2-enyl- benzene (3d and e) unsaturated pyrosulphonic acids are obtained with the double bond at C-cc and the pyro- sulphonic acid group at C-p-for the substrates (3a, b, d, and e), and the double bond at C-(3 and the pyrosulphonic acid group at C-y for (1 c).The prop-2-enyl derivatives (3b and e) yielded, besides a minor quantity of the above mentioned pyrosulphonic acids, mainly 2-arylprop-1 -ene-3-sulphonic acids, and substrate (3d) the cis-and trans-isomer of the cyclic sulphonate sulphate anhydride (5d). All these sulpho-products result from direct attack of SO3 on the side-chain double bond. 9-[(€)-prop-1 -enyl]anthracene yields sodium (€)-1 -(g-anthryl)prop- 1-ene-3-sulphonate as the main product. It is suggested that this product results from initial attack of SO, at the 10-position of the anthryl group followed by the reaction sequence proposed in the preceding paper. The behaviour of the presently investigated anthracene derivatives is compared with the behaviour of both the corres- ponding saturated anthracene analogues and the corresponding side-chain benzene analogues. RECENTLYwe reported on the behaviour of some 9-alkylanthracenes towards dioxan-SO, as sulphonating medium.1*2 The formation of the products was ex-plained in terms of the initial formation of the cor-responding 9-(alk-l-eny1)anthracenesin a redox reaction, which intermediates were then rapidly sulphonated. In some cases, depending on the structure of the alkyl group, this intermediate could be detected in the reaction mixture by lH n.m.r.It was thought of interest to study the sulphonation of some of these intermediates and to compare their behaviour with that of the cor- responding benzenes. RESULTS The reactions of 9-vinyl-, 9-[(E)-but-2-enyl]-, t Y-[(E)-prop- l-enyll-, and 9-(prop-2-eny1)-anthraceneand those of the corresponding benzene derivatives of the last two compounds, viz.(E)-prop-l- and -2-enylbenzene, with ca. 1 equiv. [2H,]dioxan-S0, complex in [2H,]dioxan have been investigated at 17 "C. The composition of the reaction mixtures was determined both during and after the reaction by lH n.ni.r. niulticomponent analy~is.~~ 4 The lH n.m.r. data of the investigated substrates and the products are listed in Tables 1 and 2, respectively. In the reaction mixtures of 9-vinyl- and 9-[(E)-prop-l- enyllanthracene with dioxan-SO, considerable amounts, in those of 9-(prop-Z-enyl)- and 9-[(E)-but-2-enyl]-anthra-cene and (E)-prop-l-enylbenzene only small amounts, of un-7 The (E)-configuration is based on the use of (E)-l-chlorobut- 2-ene and (E)-1-bromoprop-1-ene respectively as starting com- pound in the synthesis of these substrates.With 9-[(E)-prop-l- enyl]anthracenc this assignment is supported by the observable known (probably polymeric) products were present. These types of products are absent in the reaction of prop-2-enyl-benzene with dioxan-SO,. 9- VinyZanthracene.-The reaction of 9-vinylanthracene yielded as detectable product (E)-(9-anthry1)ethylenepyro-sulphonic acid.@ 11 The assignment of this pyrosulphonic acid was based mainly on the positions of the two vinylic hydrogens and on double-resonance experiments with these hydrogens. The (E)-configuration is based on the observable vinyl coupling with J 16 Hz.9-[(E)-Prop-l-enyZ]anthracene.-The reaction of 9-[(E)-prop- l-enyl] anthracene with dioxan-SO, has been carried out at a lower substrate concentration than that of the other substrates (0.04 instead of 0.8~)to reduce dimer and polymer formation. The main isolated product is sodium (E)-I-(9-anthryl)prop-l-ene-3-sulphonate(vinylic J 16 Hz). 9-(Prop-2-eny2)unthracene.-The reaction of 9-(prop-2-eny1)anthracene yielded 5 f2% unconverted substrate, 86 f4% 2-(9-anthryl)prop-l-ene-3-sulphonicacid (6b) (see Scheme 1) T[ and 9 f2% 2-(9-anthryl)prop-l-ene-l-pyrosulphonic acid (4b) .** 9-[(E)-But-2-eny~anlhracene.-Inthe reaction of 9-[ (E)-but-2-enyllanthracene (38 f3% unconverted substrate) two pyrosulphonic acids have been obtained, viz.(E)-and (2)-1-(9-anthryl)but-2-ene-3-pyrosulphonicacid in yields of 14 f2 and 48 f3%, respectively. (E)-Prop-l-enyZbenzene.-The sulphonation mixture of (E)-prop-l-enylbenzene consisted of 40 f3% unconverted substrate, 48 f3% of the trans-isomer of the cyclic sulphonate sulphate anhydride (5d) (see Scheme l),the trans assignment of which is based on the doublet (J 11 Hz) at 11 The same product, but much less contaminated, has been obtained on reaction of 1-(9-anthryl)-l-hydroxyethanewith dioxan-SO,. It is likely that initially 9-vinylanthracene is vinyl coupling with J 16 Hz. $ In the reactions with [*HJdioxan-SO, complex in [lH,]-formed by dehydration of this substrate. Apparently 9-vinyl- dioxan no dioxan dedomposition products were formed.snthracene is then sulphonated rapidly relative to its rate of form-The differences in the chemical shifts between hydrogens attached to a carbon which carries a sulphonic or a pyrosulphonic acid group are only small, e.g. the methyl hydrogens of MeS,O,H are 21 Hz to lower field than those of MeS0,H.5 So,from the observed chemical shifts for the hydrogens under discussion no distinction can be made between a sulphonic and pyrosulphonic acid group. The requirement of ca. 2 equiv. of SO, indicates the formation of the pyrosulphonic acid, and its formation is further supported by mechanistic reasons (see Discussion section). ation thus rendering its concentration low, and this will accord- ingly lead to a lower degree of polymer formation than upon starting with 9-vinylanthracene proper.7 'The assignment of (6b) containing a sulphonic acid group is based on the use of 1 equiv. SO,.** The configuration at the double bond could not be established in the absence of a vinylic coupling. It is thought to be E in view of the similarity in the chemical shifts of the @-hydrogens of (2a and b) (see Table 2). J.C.S. Perkin I1 TABLE1 lH N.m.r. data of the alkenylarenes in [2H,]dioxan 6 LCom-7pound 1-and 8-H 0 a-H a'-H 9-H Q y-H 6-H 'Q (3a) 8.42 (m) ca. 7.6 (1 H, m) 5.73 (1H, dd) 6.07 (1 H, dd)(3b) 8.27 (m) 2.37 (3 H, s) 5.27 (1 H, s)5.89 (1 H, s)(3c) 8.58 (m) 5.32 (2 H, m) 6.58 (1H, m) 5.16 (1H. m) 1.85 (3 H, d) (34 6.39 (1H, m) 6.51 (1H, m) 2.01 (3 H, d) (34 2.32 (3 H, s) 5.27 (1 H, s)5.67 (1 H, s)(8) 8.30 (m) 7.20 (1 H, d) 6.45 (1H, dq) 1.55 (3 H, dd) 2-, 3-, 6-, and 7-H of the 9-alkenylanthracenes give a multiplet of a total width of 15 Hz centred at 6 7.60 f0.05,and 4- and 5-H a multiplet of 15 Hz width centred at 6 8.14 f0.05.10-H exhibits a singlet which for the hydrocarbons is at 6 8.51 &-0.04, but for the sulphonated products (see Table 2) is at 8.60 & 0.02. a, p, etc. refers to the carbon of the side-chain. In the prop-2-enyl derivatives a'-C represents the sp3 carbon, and p-C the terminal carbon of the double bond. e The aromatic hydrogens exhibit a multiplet at 6 7.3-7.9. TABLE 2 lH N.m.r. data of the sulphonated products 6 I h Product Solvent 1-and 8-H 0 a-H Q a'-H p-H y-H Q 6-H Q (4a) [2H,]Dioxan 8.37 (m) 8.61 (1 H, d) 7.26 (1H, d) (4b) [2H8]Dioxan 2.81 (3 H, s) 6.90 (1H, s) (4b) [2H8]Dioxan 8.39 (m) 6.78 (1H, s) 4.59 (2 H, s) 6.50 (1H, s) (E)-(4c) [2Ha]Dioxan 8.20 (m) 3.60 (2 H, d) 6.50 (1H, t) 2.40 (3 H, s) (2)-(4c) [2Hs] Dioxan 8.20 (m) 4.50 (2 H, d) 5.90 (1H, t) 2.40 (3 H, s) (4d) [2H8]Dioxan d 6.84 (1H, s) 2.45 (3 H, s)cis-(5d) [2H8]Dioxan d 6.08 (1H, d) 4.59 (1H, dq) 1.46 (3 H, d)trans-(5d) [2H8]Dioxan d 6.80 (1 H, d) ca.4.6(m) 1.53 (3 H, d)(4e) [2Ha]Dioxan d 2.70 (3 H, s) 6.96 (1H, s)(6e) [2H8]Dioxan d 4.54 (2 H, s) 5.76 (1H, s) 6.01 (1 H, s)(7e) [2H8]Dioxan d 5.36 (2 H, s) 7.14 (1H, s)(9) [2H,]Dioxan 8.48 (m) ca. 7.6 (1H, d) 6.26 (1H, dt) 4.46 (2 H, d) (1)f [2H,]Dimethyl sulphoxide d 6.35 (1H, m) 3.55 (2 H, m) (2a) [2H,]Dimethyl sulphoxide d 5.41 (1H, d) 2.88 (1H, dq) 1.03 (3 H, d) (2b) [2H,]Dimethyl sulphoxide d 5.92 (1H, d) 2.8 (1H, m) 1.15 (3 H, d) (2c) [2H,]Dimethyl sulphoxide d 4.65 (1H, d) 2.8 (1H, m) 0.84 (3 H, d) o*b As Table 1.Only the positively assigned absorptions are listed. See footnote c of Table 1. These are in fact the values of (9) formed in the reaction of 9-propylanthracene with dioxan-SO, in dioxan,2 as it appeared that the absorptions of (9) in the spectra of the sulphonates obtained on reaction of (8) and 9-propylanthracene are identical. f Data from ref. 6. 6 6.13 for the a-hydrogen,* 10 f2% of the cis-isomer, lysed * as is in fact observed. The three products result- based on the doublet (J1.5Hz) at 6 6.76 for the a-hydrogen,* ing are tentatively assigned asthe two possible disodium salts and ca.2yo of l-phenylprop- l-ene-2-pyrosulphonic acid as of the sulphate of l-phenyl- l-hydroxypropane-3-sulphonate, detectable products.? The signals of the anhydrides (5d) disappeared after 6 h. The assignment of the anhydride structure (5d) is based on the following evidence. First, sulphonation with 1 equiv. SO, gives substrate conversion and product formation both of GU.50%, illustrating that 2 ml of SO, are required per mol of substrate. Secondly the positions and multi-plicities of the lH n.m.r. signals of the products obtained (see Table 2) and their agreement with those of the cyclic sulphonate sulphate anhydride ( 1) obtained from 2,6-di- chlorophenylethylene (see Table 2).' Finally on pouring the mixture into ice-water followed by neutralization with NaOH the anhydrides should be hydro- * On the assumption that the anhydride (5)has a chair structure similar to that of cyclohexane it follows that the a-and (3-side-chain carbons and their hydrogens in the trans-isomer are approximately in one plane, whereas for the cis-isomer they are not.Using the Karplus equation it then follows that the coupling constant between the vicinal a-and @-hydrogens is greater with the trans-viz. 65% (2a) and 15% (2b), and the sodium salt of 1-than with the cis-isomer. phenyl-l-hydroxypropane-2-sulphonate(20%) (2c).$ Pre-t Anhvdrides 15) were also detected as intermediates in the reaction of 3-phenylpropan-1-01 with concentrated H2S0,, $ The assignment of the three Fischer projections (2) was eventually leading to l-(p-sulphophenyl)prop-l-ene-2-sulphonicfurther Droven bv double-resonance exDeriment on the side-chain acid as the main productqe carbon-Londed hjrdrogens.viously it was only reported that the sulphonation of prop- 1-enylbenzene with dioxan-SO, in ethylene chloride yields 1 -phenylprop- 1-ene-Zsulphonate. Pro~-2-eutyZbenzene.-The sulphonation of prop-2-enyl-benzene leads to the formation of two products, viz. 92 f 3% 2-phenylprop-1-ene-3-sulphonicacid (6e) * and 8 f3% 2-phenylprop-1-ene- 1-pyrosulphonic acid (4e) (see Scheme 1).t On using an excess of dioxan-SO, the disulphonic anhydride (7e) is obtained, which is thought to be formed by dehydration of 2-phenylprop- 1-ene- l13-disulphonic acid ; this disulphonic acid would result from the sulphonation of the initially formed 2-phenylprop- 1-ene-3-sulphonic acid.The presence of the compounds (6e) and (7e) was established a; Ar = 9-An, R1 = R2 =H b; Ar = 9-An, R1 = H,R2 =Me c; Ar = 9-AnCH2,R’ = Me,R2 = H d; Ar = Ph, R1 = Me,R* =H e; Ar = Ph, R1 = H,R* = Me 25 DISCUSSION Mechanism of Product Formation.-The formation of the products obtained in the reactions of 9-vinyl- (3a), 9-(prop-2-enyl)- (3h), and 9-[ (E)-but-2-enyl]-anthracene (3c) and (E)-prop-1- and prop-2-enylbenzene (3d and e) with dioxan-SO, in dioxan may be explained in terms of the mechanism depicted in Scheme 1.The initial step is the transfer of SO, from the dioxan-SO, complex to the double bond with formation of (I). This dipolar inter- mediate cannot undergo an intramolecular proton shift of the hydrogen attached to the carbon carrying the sulphonate to the sulphonate oxygen.: By analogy with ‘R2 (4) Ic-so2 A r-C ‘0\/0--so 2 ,C--SO3H c-so2 Ar-C, Ar-C ‘0 -C \\ / c--s02 (7e) SCHEME1 by field-ionization and field-desorption mass spectrometry. With these techniques signals were found at m/e 198 and 260 which agree with the molecular weights of compound (6e) and (7e), respectively. Moreover, the high-resolution mass measurement of m/e 260 confirmed the elemental composi- tion of (7e) (Found: m/e, 259.980. Calc. for C,H,S,O,: M,259.981 3).The products obtained on reaction of prop- 2-enylbenzene with dioxan-SO, are similar to those reported by S~ter.~ The only difference is that Suter after working up, obtained 2-phenylprop- 1 -ene- 1,5-disulphonate as prin- cipal product, which apparently results from hydrolysis of (7e). * The assignment of (6e)as a sulphonic acid is based on the use of 1 equiv. SO,.t The configuration at the double bond could not be established in the absence of vinylic coupling but is thought to be E in view of the similarity in the chemical shifts of the @-hydrogens in (4a and e) (see Table 1). aprotic aromatic sulphonation,j: it is proposed that (I) reacts with SO, to give (11) [step (2)]. This intermediate can either undergo an intramolecular proton shift of the hydrogen attached to the carbon carrying the pyro- sulphonate group with formation of the unsaturated pyrosulphonic acid (4) [step (3)], as observed with the substrates (3a--e), or give ring-closure [step (4)] with formation of cyclic sulphonate anhydrides, as observed on starting with (3e). In the case of substrates with the prop-2-enyl side-chain (3b and e), (I) may also undergo A comparable geometric orientation exists in the l-arenium- 1-sulphonate a-complex which results on reaction of e.g.p-di-chlorobenzene with SO, in aprotic solvents.10 This a-complex does not allow an intramolecular proton shift. Instead it reacts with an additional molecule of SO, with formation of the 1-arenium-2-pyrosulphonate a-complex which now undergoes an intramolecular proton shift with formation of the arenepyro- sulphonic acid. an intramolecular proton shift from the methyl group to the sulphonate oxygen via a six-membered transition state to yield (6) [step (5)]. An excess of dioxan-SO, leads to the formation of the anhydride (7) in the case of prop-2-enylbenzene, but not with 9-(prop-2-enyl) anthra- cene, possibly for steric reasons.Substrate (3c) yields (E)-and (Z)-l-(g-anthryl)but- 2-ene-3-pyrosulphonic acid [(E)-and (2)-(4c), respect- ively] in a ratio of 0.28 : 1. The high yield of the Z-isomer is unexpected in view of the steric interaction between the sulpho and the anthryl group. It should be stressed that (E)-1-(9-anthryl) but -2-ene- 1-sulphonic acid qo3, J.C.S.Perkin I1 The formation of sodium (E)-l-(9-anthryl)prop-l-ene-3-sulphonate (9) from 9-[(E)-prop-l-enyl]anthracene (8) may be explained as depicted in Scheme 2.* In the first step SO, is transferred to the 10-position of anthra- cene [step (7)]. The resulting a-complex (111) is stabil-ized by hyperconjugation, and has weakly acidic y-hydrogens. Electrophilic sulphonation of one of these hydrogens yields the a-complex (IV) [step (S)] which loses SO, with formation of the sulphonic acid [step (9~.Comparison with Related Substrates.-The reaction of 9-et hylant hracene yields 1-(9-ant hry1)et hane- 1-sulphonic (9) SCHEME2 is not formed in the reaction. This product would result from initial addition of SO, to the 10-position of anthracene followed by subsequent steps, as proposed for the formation of 1-(9-anthryl)prdpane-l-sulphonic acid from 9-propylanthracene [see steps (l),(3),and (6)in Scheme 2 of ref.21. The formation of (E)-and (Z)-(4c) together with the absence of (E)-l-(9-anthryl)but-2-ene-1-sulphonic acid suggests for substrate (3c) a higher reactivity at C-y of the isolated double bond compared with the 10-position of the anthryl group. * For a more complete discussion of the reactions depicted in Scheme 2, see ref. 2. acid and (E)-(9-anthry1)ethylenepyrosulphonic acid.2 The latter was also obtained as the sole product on re- action of 9-vinylanthracene with dioxan-SO,. The same product(s) is also formed in the reactions of 9- [(I?)-prop-1 -enyl]- and 9-propyl-anthracene, viz.(E)-1-(9-anthryl)prop-l-ene-3-sulphonicacid, and of 9-(prop- 2-eny1)- and 9-isopropyl-anthracene, viz. both 2-(9-anthryl)prop-l-ene-3-sulphonicacid and 2-(9-anthryl)- prop-1-ene-1-pyrosulphonicacid. The observation of these products supports the proposition that the three presently investigated substrates, i.e. 9-vinyl-, 9-[(E)-prop-1 -enyl]-, and 9-prop-2-enyl-anthracene, are inter- mediates in the dioxan-SO, reactions of 9-ethyl-, 9-propyl-, and 9-isopropyl-anthracene, respectively. The sulphonation of both 9-vinylanthracene and vinyl- benzene yielded, as for 9-(prop-2-enyl)anthraceneand prop-2-enylbenzene, products with structurally identical side-chains, viz.l-arylethylene-2-sulphonicacids * for the vinyl derivatives, and Z-arylprop- 1-ene-1-pyrosulphonic acids (5b and e) and 2-arylprop-l-ene-3-sulphonicacids (6b and e) for the prop-2-enyl derivatives. The form- ation of these products with the same side-chain struc- ture illustrates that only the addition of SO, to the p-carbon of the side-chain [step (l),Scheme 13 leads to the formation of products. The products formed in the sulphonation of 9-[ (E)-prop-l-enyllanthracene and (E)-prop-l-enylbenzene are completely different, vix. (E)-1-(9-anthry1)prop- l-ene- 3-sulphonate and the cyclic sulphonate sulphate anhy- dride (5d), respectively. This difference may be ex-plained in terms of the higher rate of SO, addition to the 10-position of the anthryl group (the subsequent reaction sequence, see Scheme 2, being fast) than to the p-carbon of the side-chain of 9-[ (E)-prop-l-enyllanthracenewhich itself is apparently higher than to the p-position of (E)-prop- l-enylbenzene.EXPERIMENTAL Malerials.-9-Vinylanthracene and (E)-prop-1-and -2-enylbenzene were obtained from Aldrich. The reactions to obtained 9-[ (E)-prop- l-enyll-, 9- (prop-2-enyl) -, and 9-[ (E)-but-2-enyll-anthracene were carried out as described '9before; the Grignard reactions yielded 9-alltenyl-9-hydroxy-9,lO-dihydroanthracenes.9-[(E)-Prop- l-enyl] and 9- (prop-2-enyl) -9-hydroxy-9,lO-dihydroanthracene were found to dehydrate during their purification on a neutral alumina column; 9-[ (E)-but-2-enyl]-9-hydroxy-9,1O-dihy-droanthracene was dehydrated as described before.' The * The reaction of vinylbenzene with dioxan-SO, complex in ethylene dichloride yielded, after basic hydrolysis, sodium 2-phenylethylene-l-suiphonateand sodium 2-hydroxy-2-phenyl-ethanesulphonate.ll alkenylanthracenes were further purified by recrystalliz- ation from ethanol.Reaction Procedures.-The reactions with dioxan-SO, complex have been carried out as described before.' 1H N.M.R. Analysis.-The spectra were recorded with a Varian HA-100 or XL-100 spectrometer; the chemical shifts (6) of [2H,]dioxan solutions are relative to external, neat tetramethylsilane (capillary), and those of C2H6]-dimethyl sulphoxide solutions relative to internal tetra-methylsilane.Mass Spectroscopy .-The field-ionization and field-desorption mass spectra were recorded on a Varian MAT 7 11 double-focusing mass spectrometer equipped with a com- bined e.i.-f.i.-f.d. source. For the f.d. experiments emis- sion controlled f.d. was used at a threshold of 10 nA. The samples of the [2H,]dioxan solutions were loaded with the dipping technique. The f.i. measurements were obtained with a direct-insertion probe at 50 "C. Exact mass measure- inents were performed with a resolution of 10.000 (10% valley definition). [8/1960 Received, 10th November, 19781 REFERENCES 1 Part 73, F. van de Griendt and H. Cerfontain, preceding paper.F. van de Griendt and H. Cerfontain, J.C.S. Perkin I1 1980, 13. H. Cerfontain, A. Koeberg-Telder, C. Kruk, and C. Ris, Analyt. Chem., 1974, 46, 72. H. Cerfontain, A. Koeberg-Telder, C. Ris, and C. Schenk, J.C.S.Perkin 11, 1975, 966. 6 E. A. Robinson and V. Silberberg, Canad. J. Chem., 1966,44, 1437. 6 A. Koeberg-Telder and H. Cerfontain, J.C.S. Perkin II, 1976, 1776; A. Koeberg-Telder, F. van de Griendt, and H. Cer-fontain, ibid., in the press. J. C. Sheehan and U. Zoller, J. Org. Chem., 1975, 40, 1179. F. G. Bordwell and &I.L. Peterson, J. Amer. Chem. SOC., 1954,76, 3952. @ C. M. Suter and W. E. Truce, J. Amer. Chem. SOL, 1944, 66, 1105. lo J. K. Bosscher and H. Cerfontain, Rec. Trav. chim., 1968, 87, 873; J. Chem. SOC.(B), 1968, 1524. l1 F. G. Bordwell and C. S. Rondestvedt, jun., J. Amer. Chem. SOC.,1948, 70, 2429.

ISSN:1472-779X    

DOI:10.1039/P29800000023

出版商:RSC    

年代:1980

数据来源: RSC