Organometallics 1983,2,391-394
391
metal complexes. One of the earliest reports on such a seems likely that the naphthalene or l-methylnaphthalene in our process also functions as more than a mere soluble system involved the reduction of CrC1, by Na-Cl,& under electron carrier during the reduction process. Similar high pressures of CO at 25 "C to ultimately give a 10% reductions of MCl, carried out in the absence of naphyield of cr(co)6.15 However, undoubtedly the most important previous contribution in this area, especially in thalene in the presence of CO at atmospheric pressure give terms of its influence on the present study, was Datta and zero or exceedingly poor yields of M(CO)6-. It is noteworthy that neutral bis(naphtha1ene)vanadium has been Wreford's observation that ( d m ~ e ) ~ T a Ccould l, be reductively carbonylated at atmospheric pressures and 25 reportedly obtained by the reduction of VCl, by Li-Np.a OC by Na-CloHa to provide good yields of ( d m ~ e ) ~ T a Also, neutral bis(arene) complexes of Nb and T a are (CO)2C1.16 This study provided the first indication that known,g but the only bis(arene)metalate ion presently group 5 metal halides could undergo efficient reductive established is apparently V(C6H6)2-.'o Although the recarbonylation at atmospheric pressure. Efforts are presactions of bis(arene)niobium and tantalum complexes with carbon monoxide have not yet been reported, Calderazzo ently underway to determine whether our low-temperature and Cini showed in 1965 that bis(mesitylene)vanadium(O) reductive carbonylation procedure can be extended to reacted with CO (at 35 OC (100 atm.)) to give the disprogroup 4 metal comp1exes.l' portionation product [(me~itylene)V(CO)~][V(CO)~]." Acknowledgment. We thank the donors of the PeEarlier it had been reported, apparently incorrectly, that troleum Research Fund, administered by the American bis(toluene)vanadium(O) gave V(CO)6under similar conChemical Society, and the National Science Foundation ditions.12 Interestingly, tris(cyclooctatraene)niobate(1-) (Grant CHE 82-10496)for continuing support of this work. provided Nb(CO)6- in an unspecified yield when heated under high pressures of CO a t 110 "C in THF.', Our Registry No. 1, 57288-90-1; 2,67292-38-0; 3, 15602-40-1;4, suggestion that the intermediates in our two-step reductive 12189-44-5;5, 84280-29-5;6, 82581-56-4;7, 84280-30-8;8, carbonylation procedure are M(C10Ha)2-is also consistent 12189-43-4. with the observation that both naphthalene groups in Cr(C10H8)2and Mo(CloHE)2are readily displaced by CO (15)Shapiro, H.; Podall, H. E. J. Inorg. Nucl. Chem. 1962,24,925. to quantitatively produce the corresponding M(COI6 at 25 (16)Datta, S.;Wreford, S. S. Inorg. Chem. 1977,16,1134. "C and 1 atm of pressure.14 (17)Note Added in Proof: Further experiments have shown that the Alkali-metal naphthalenides have been used previously "red brown intermediate" of tantalum is not as thermally unstable as originally suggested. In one preparation, a DME solution of the interin "one-step" reductive carbonylations of early transition (8) Henrici-Olive, G.; Olive, S. J. Am. Chem. SOC. 1970,92,4831. (9)Cloke, F. G. N.; Green, M. L. H. J. Chem. SOC.,Dalton Trans. 1981, 1938. (10)Elschenbroich, G.; Gerson, F. J. Am. Chem. SOC.1975,97,3556. (11)Calderazzo, F.; Cini, R. J. Chem. SOC.1965,818. (12)Pruett, R.Y.;Whyman, J. E. Chem. Ind. (London) 1960,79,119. (13)Guggenberger, L. J.; Schrock, R. R. J.Am. Chem. SOC.1975,97, 6693. (14)Kundig, E. P.; Timma, P. L. J.Chem. SOC.,Chem. Commun. 1977, 912.
mediate wm warmed to 25 OC and maintained at this temperature for 12 h under a nitrogen atmosphere. Carbonylation of the resulting mixture at 1 atm P and room temperature provided approximately 30% yields of [Et,N][Ta(CO)6]. When the same procedure was attempted with niobium, no formation of Nb(CO)6- occurred. Also, a sodium benzophenone reduction of TaC16 in DME at -70 "C followed by an atmospheric pressure carbonylation at -70 OC provided a 20% yield of [Et4Nl [Ta(C0)61. Very recently, we learned that another group has also developed an atmospheric pressure reductive carbonylation synthesis of Nb(CO)6-. Calderazzo, F.; Englert, U.; Pamploni, G.; Pelizzi, G.; Zamboni, R. Inorg. Chem., in press.
An Improved Synthesis of Key Intermediates in Metallole 4 8 Chemistry Georges Manuel," Guy Bertrand, and Fatiha El Anba Laboratoire des Organom6talliques, ERA 829, Universit6 Paul-Sabatier, 3 1062 Toulouse C a e x , France Received September 23, 1982
The base-induced rearrangement with Et2NLi of 6-oxa-3-metallabicyclo[3.l.0]hexanes is a convenient method for the synthesis of cyclic allylic alcohols of silicon and germanium-key intermediates of siloles and germoles. The remarkably rich chemistry of a-cyclopentadienyl transition-metal complexes has prompted chemists to investigate heterocyclopentadieny11igands.l For compara-
tive studies with carbon isologues, metalloles of group 4B are of special interest.2 However, although C-aryl-substituted 4B metalloles are ~ e l l - k n o w nnon-C-substituted ,~
(1)See, for example: Green, M. L. H. "Organometallic Compounds Z", 3rd ed.; Methuen: London, 1968,p 302. Hoberg, H.; Richter, W. J. Organomet. Chem. 1980,195,347.Mathey, F.;Mitachler, A,; Weiss, R. J.Am. Chem. SOC.1977,99,3537. Santini, C.; Fischer, J.; Mathey, F.; Mitschler, A. Inorg. Chem. 1981,20,2848.de Lauzon, G.; Deschamps, B.; Mathey, F. Nouu. J. Chim. 1980,4,683. Abel, E. W.; Nowel, I. W.; Modinos, A. G. J.; Towers, C. J.Chem. SOC.,Chem. Commun. 1973,258. Ashe, A. J., 111; Dicphouse, T. R. J. Organomet. Chem. 1980,202,C95.
(2)See, for example: Jutzi, P.; Karl, A. J. Organomet. Chem. 1977, 128,57. Abel, E.W.; Blackmore, T.; Whitley, R. J. J.Chem. Soc., Dalton Trans. 1976,2484. Muir, K.W.; Walker, R.; Abel, F. W.; Blackmore, T.; Whitley, R. J. J. Chem. Soc., Chem. Commun. 1975,698. Sakurai, H.; Hayashi, J. J. Organomet. Chem. 1973,63,C10. Jutzi, P.;Karl, A,; Burschka, C. Ibid. 1981,215,27.Herberich, G. E.; Mtiller, B.; Hessner, B.; Oschmann, W. Ibid. 1980,195,253.
0276-7333/83/2302-0391$01.50/00 1983 American Chemical Society
392 Organometallics, Vol. 2, No. 3, 1983
Manuel, Bertrand, and El Anba
Table I. Comparitive Results Observed with Methods I and I1 for the Synthesis of Compounds 5 and 6
Scheme I. Comparitive Results Observed for the Synthesis of Isomeric Compounds 7 and 7' with Methods I and I1
yield,c %
R
M
Me Me Ph Ph
Si (5a)
method IQ
method I1 b
70 70
86
Ge (5b) Si (6a) Ge (6b)
IO 78 12
Photooxygenation-reduction.9 Base-promoted rearrangement. Yield in % from the corresponding metallacyclopentene.
siloles4+ and germoles7 have been synthesized only recently. Dehydration on alumina of l-metallacyclopent-4-en-3-ols (A) appears to be the most convenient method for obtaining n o n - C - s ~ b s t i t u t e dor ~ , ~C-methylateds siloles or germoles (B)(eq 1).
M
=
-
M e z M z i
+ M e 2 M s t v OH le
Me
method I,Q M = Si M = Ge
7a, 80% 7b, 43%
7'a, 20% 7'b, 57%
method II,b M = Si 7a, 100% 7'a, 0% M = Ge 7b, 100% 7'b, 0% Photoxygenation-red~ction.~ Base-promoted rearrangement. Table 11. Comparative Results Observed with Methods I and I1 for the Synthesis of Compounds 8 and 9 ~~
8a/9a (Si)
8b/9b (Ge)
58/42 77/23
68/32 83/17
method IQ method IIb
a Photooxygenation-reduction.g rearrangement.
Base-promoted
the rearrangement in comparison to analogous reactions in the carbon series.
B
A
M e z M x M e
Results and Discussion
Si, Ge; R, R' = H, Me
The metallacyclopentenolsubstrates A may be obtained by dye-sensitized photooxygenation-reduction of the (eq 2), but this corresponding metalla~yclopent-3-ene~~~ synthesis involves the use of special equipment for generating singlet oxygeng and is not always regioselective.s
The starting epoxides 1-4 were obtained in almost quantitative yield from the corresponding metallacyclopentenes by oxidation with m-chloroperbenzoicacidlo (eq
3).
1, R = Me, R ' = R" = H 2, R = Ph, It' = R" = H 3 R = R' = R" = Me 4, R = R" = Me, R' = H M = Si, Ge
A
M = Si, Ge
We report here an improved synthesis of key intermediates ( A ) involving base-induced rearrangement of the easily available 6-oxa-3-metallabicyc10[3.1.0] hexanes 1-4.1° We will emphasize the general character and stereospecificity of this method compared with those previously rep ~ r t e d as , ~well ~ ~ as the role of the heteroatom (Si, Ge) in (3) See, for example: Braye, E. H.; HUM, W.; Caplier, I. J.Am. Chem. SOC.1964,86, 4406. Gilman, H.; Cottis, S. G.; Atwell, W . H. Ibid. 1964, 86, 1596. Curtis, M. D. Zbid. 1969, 91, 6011. Atwell, W. H.; Weyenberg, D. R.; Gilman, H. J. Org. Chem. 1967,32,885. Brunet, J. C.; Demey, N. Ann. Chim. (Paris)1973,4123. Barton, T. J.; Gottaman, E. E. Synth. Inorg. Met. O g . Chem. 1973, 3, 210. Gilman, H.; Atwell, W. H. J. Organomet. Chem. 1964,2,291. Okinoshima, H.; Yamamoto, K.; Kumada, M. J. A m . Chem. SOC.1972,94,9263. (4) Barton, T. J.; Burns, G. T. J. Organomet. Chem. 1979, 179, C17. (5) Laporterie, A.; Mazerolles, P.;Dubac, J.; Iloughmane, H. J. Organomet. Chem. 1981,206, C25. Laporterie, A.; Dubac, J.; Mazerolles, P.; Iloughmane, H. J. Organomet. Chem. 1981,216, 321. (6) Burns, G. T.; Barton, T. J. J. Organomet. Chem. 1981,209, C25. (7) Laporterie, A.; Manuel, G.; Dubac, J.; Mazerolles, P.; Iloughmane, H.J. Organomet. Chem. 1981,210, C33. (8) Laporterie, A.; Manuel, G.; Dubac, J.; Mazerolles, P. Nouu. J. Chim. 1982, 6, 67. (9) Laporterie, A.; Dubac, J.; Mazerolles, P. J. Organomet. Chem. 1980,202, C89. (10) Manuel, G.; Mazerolles, P.; Florence, J. C. C. R. Hebd. Seances Acad. Sci. Ser. C 1969,269,1553. Manuel, G.; Mazerolles, P.; Florence, J. C. J. Organomet. Chem., 1971, 30, 5. Manuel, G.; Mazerolles, P.; Lesbre, M.; Pradel, J . P. Ibid. 1973, 61, 147. (11) Mazerolles, P.; Manuel, G. Bull. Soc. Chim. Fr. 1966, 1, 327. Mazerolles, P.; Manuel, G.; Thoumas, F.; C. R. Hebd. Seances Acad. Sci., Ser. C, 1968, 267, 619. Manuel, G.; Mazerolles, P.; Cauquy, G. Synth. React. Znorg. Met. Org. Chem. 1974, 4, 133.
The base-promoted rearrangements were carried out with lithium diethylamide, a poor nucleophilic but a strong basic reagent. Under these conditions, the desired allylic alcohols 5 and 6 were obtained in good yield from derivatives 1 and 2 (R' = R" = H; eq 4;Table I).
1;2
l a , 5a, M l b , 5b, M 2a, 6a, M 2b, 6b, M
576 = Si, R = Me = = =
Ge, R = Me Si, R = Ph Ge, R = Ph
The results observed with C-dimethylated derivatives 3 are more interesting since the base-induced rearrangement leads to only one product 7 (Si, 83%, and Ge, 76% yield). Indeed, formation of the isomeric exocyclic ethylenic derivative 7' was not observed at all (Scheme I). The stereospecificity of the base-promoted rearrangement should be of great interest to elucidate, for example, the mechanism of the dehydration in the case of the Cmethylated silole and germole.s Indeed, allylic alcohol 7 was never obtained in the pure isomeric form from the previously reported synthetic method.s In the case of nonsymmetrical epoxides 4, two isomeric allylic alcohols 8 and 9 (Si, 85%, and Ge, 70% yield) were obtained (eq 5 ) . In this case, although the base-induced
Organometallics, Vol. 2, No. 3, 1983 393
Key Intermediates in Metallole 4B Chemistry
rearrangement is not stereospecific, the selectivity is better than that in the photooxygenation-reduction methode (Table 11).
Me
4
9
8
It is interesting to note that the reaction of carbon epoxides with strong bases such as lithium diethylamide may take a number of courses depending on the structure of the oxirane. With the carbon isologues of derivatives 1 and 4, Crandall et al.12J3 reported the formation of several products in poor yield. R
8.4% 65%
R=H
R=Me
2.5%
7.4%
36%
These contrasting results between the carbon and the silicon or germanium series could be rationalized by a mechanism involving preliminary abstraction of a proton from the position a to M. The presence of a silicon or a germanium atom increases the lability of the hydrogen in the a-position (probablybecause of the stabilizationof the negative charge, in the transition state, by empty 3d (Si) or 4d (Ge) orbitals14)and, in a similar way, the a-ethylenic bond in the final product could be stabilized (pr-da stabilization). t
M = C, Si, Ge
The choice of deprotonating agent is critical since the more nucleophilic organolithium compounds tert-butyllithium and methyllithium react with l a to give ringopening products presumably by attack at silicon.
la
R
10
R = Me, t-Bu
Conclusion The base-induced rearrangement of 6-oxa-3-sila- or 6oxa-3-germabicyclo[3.l.O]hexanes appears to be a very simple and stereoselective method for obtaining different precursors of 4B metalloles. These results emphasize the role of the Si or Ge heteroatom;in contrast with the carbon (12)Crandall, J. K.; Chang, L. H. J . Org. Chem. 1967, 32, 435. (13) Crandall, J. K.;Lin, L. H.J. Org. Chem. 1968, 33, 2375. (14)Attridge, C. J. Organomet. Chem. Rev., Sect. A 1970, 5, 323.
series, we only observed the formation of cyclic allylic alcohols. Experimental Section General Data. All boiling points reported in this section are uncorrected. The infrared spectra (liquid film) were obtained on a Perkin-Elmer Model 457 spectrophotometer. The 'H NMR spectra were obtained on a Varian Associates EM 360 A nuclear magnetic resonance spectrometer. Chemical shifts are reported in 6 units, parts per million (ppm) downfield from internal tetramethylsilane. All chemicals used are of commercial origin unless otherwise indicated. 6-Oxa-3-sila- (or 6-oxa-3-germa-) bicyclo[3.1.0]hexanes (1-4) were prepared as described'O from corresponding 1-sila- (or germa-) cyclopent-3-enes." General Procedure. A lOO-mL, dry, three-necked, roundbottomed flask equipped with a serum cap, a mechanical stirrer, and a gas inlet was flushed with nitrogen and charged with 2.3 g (30 mmol) of dry diethylamine, 20 mL of dry pentane, and 10 mL (25 mmol) of n-butyllithium (or methyllithium) in hexane. After the mixture had been cooled to 20 OC, 10 mmol of epoxides 1-4in 30 mL of dry diethyl ether was added. The reaction mixture was refluxed for 10h Then, 10 mL of a saturated aqueous solution of NaCl was slowly introduced, and the brown color disappeared. The organic phase was washed four times with water. After removal of the solvents, the residue was distilled under vacuum. It is necessary to use an excess of amine for complete transformation of alkyllithium into lithium diethylamide because alkyllithium readily reacts with epoxides 1-4 to give linear products 10. Diethylamine did not react with epoxides 1-4 even at 100 "C in a sealed tube. 1,l-Dimethyl-1-silaor 1,l-dimethyl-1-germacyclopent-4en-3-01s(5a or 5b) and 1,1,3-or 1,1,4-trimethyl-l-silacyclopent-4-en-3-01sor 1,1,3- or 1,1,4-trimethyl-l-germacyclopent-4-en-3-01s(sa,9a, 8b, or 9b) were previously reported.8 1,l-Diphenyl-l-silacyclopent-4-en-3-01 (sa): bp 152 "C (0.3 mm); 'H NMR (CDC13)6 1.30 (AB part of ABX system, JAB= 15 Hz, Jm = 8 Hz, JBx= 6 Hz, 2 H, SiCH,), 4.5 (br s, 1H, OH), = ,10 4.8 (m, 1H, CHOH), 6.6 (A'B' part of A'B'X system, J A ~ Hz, JAtx = JBtx =2 Hz, 2 H, CH=CH), 7.1 (m, 10 H, PhSi); IR (cm-l) 3450 (s), 3120 (w), 2980 (s), 2890 (m), 1560 (w), 1450 (m), 1400 (w), 1340 (w), 1280 (w), 1140 (m), 1040 (m),910 (w),880 (m), 760 (m), 720 (m). Anal. Calcd for C16H160Si:c, 76.15; H, 6.39. Found: C, 76.03; H, 6.41. l,l-Diphenyl-l-germacyclopent-4-en-3-ol (6b): bp 167 "C (0.3 mm); 'H NMR (CDC13)6 1.55 (AB part of ABX system, JAB = 14 Hz, Jm = 8 Hz, JBx = 6 Hz, 2 H, GeCHJ, 4.7 (br s, 1 H, OH), 4.9 (m, 1H, CHOH), 6.6 (A'B' part of A'B'X system, JAtB, = 10 Hz, JAx = JBx = 2 Hz, 2 H, CH=CH), 7.2 (m, 10 H, PhGe); IR (cm-') 3450 (s), 3080 (m), 3060 (m), 3000 (w), 1540 (w), 1490 (m), 1440 (s), 1140 (m), 1100 (m), 1020 (s), 870 (m), 800 (s), 750 (s), 700 (8). And. Calcd for Cl6H&e0 c, 64.72; H, 5.43. Found C, 64.83; H, 5.44. 1,1,3,4-Tetramethyl-l-silacyclopent-4-en-3-01 (7a): bp 90 "C (24 mm); 'H NMR, ref 8; IR (cm-') 3360 (s), 2950 (s), 1585 (m), 1440 (m), 1400 (w), 1360 (m), 1250 (m), 1180 m, 1110 m, loo0 m, 930 m, 900 w, 830 m, 680m, 640 (m). Anal. Calcd for C&IlSOSi: C, 61.47; H, 10.32. Found: C, 61.57; H, 10.30. 1,1,3,4-Tetramethyl-lgermacyclopent-4-en-3-01(7b): bp 101 "C (30 mm); 'H NMR, ref 8; IR (cm-') 3350 (s), 2950 (e), 1595 (m), 1450 (m), 1370 (m), 1240 (m), 1180 (s), 1170 (m), 1000 (m), 940 (m), 820 (s), 740 (w), 700 (w), 660 (w),600 (m). Anal. Calcd for C8H16GeO: C, 47.85; H, 8.03. Found: C, 47.98; H, 8.00. 4-(Trimethylsilyl)but-l-en-3-ol(lO). A flask with side arm (septum closure) and condenser was charged with 10 mL (20 mmol) of 2 M solution of methyllithium in diethyl ether. To this solution was slowly added 1.3 g (10 mmol) of 6-oxa-3,3-dimethyl-3-silabicyclo[3.l.0]hexane(la)in 10 mL of dry hexane. The reaction mixture was refluxed under nitrogen atmospher for 5 h, hydrolyzed, and extracted with EGO,and the extracts were dried over anhydrous Na2S04. Solvents were removed by distillation, and the residue was distilled to give 1.0 g of alcohol 10 (77%): bp 85 OC (49 mm); n2OO1.4421; a2040.8507"; 'H NMR (CC14)6 0.03 (s, 9 H, CH,Si), 0.9 (dd, 2 H, SiCHJ, 2.9 (br s, 1H, OH), 4.16 (m, 1 H, CHOH), 5.0 (m, 2 H, CH2=C), 5.8 (m, 1 H, C=CH); IR (cm-') 3350 (s), 3080 (m),2960 (s), 2900 (s), 1630 (m), 1400 (s), 1250 (s), 1200 (m), 1040 (s), 870 (s), 760 (m),690 (5). Anal.
394
Organometallics 1983,2, 394-399
Calcd for C7HIROSi: C, 58.17;H, 11.19.Found: C, 58.02; H, 11.05. ..
2b, 51343-35-2; 3a, 33459-96-0;3b, 51343-31-8;4a, 33460-17-2;4b, 51343-30-7; 5a, 77225-27-5;5b, 11225-28-6; 6a, 71404-32-5; 6b, 84279-87-8;7a, 82763-88-0; 7b, 82763-89-1; 7'8, 82763-90-4; 7'b, 82763-91-5;8a, 82763-85-7;8b, 82763-86-8; 9a, 82763-87-9; 9b,
Acknowledgment. The authors are grateful to Dr. Mazerolles and Pr. J. Dubac for helpful discussions. Registry No. la, 65181-02-4; lb,51343-29-4; Za, 51343-26-1;
82764-03-2;10, 18269-52-8.
Asymmetric Synthesis of trans-2,3-Diaryloxiranes. Benzylidene Transfer from Chiral Arsonium Ylides David G. Allen and Stanley Bruce Wild" Research School of Chemistry, The Australian National University, Canberra, A. C.T., Australia 2600 Received August 13, 1982
Potassium diphenylarsenide reacts with (-)-menthyl chloride in boiling tetrahydrofuran to produce (+)-diphenylneomenthylarsine. Quaternization of this compound with benzyl bromide affords (+)benzyldiphenylmenthylarsonium bromide, which upon reduction with lithium aluminium hydride gives the epimeric (-)-diphenylmenthylarsine. Equilibrium concentrations of the semistabilized benzylidene ylide derived from the menthylarsonium salt, and from a variety of other optically active arsonium salts containing asymmetric arsenic atoms, react with prochiral aromatic aldehydes to produce good to excellent yields of trans-2,3-diaryloxiraneshaving optical purities of up to 41%. The degree of asymmetric induction depends upon the nature of substituents within the ylide and on the substrate molecule and upon reaction conditions. The stereochemistry of the products has been rationalized in terms of the conformational differences between the intermediate erythro-betaines, Arsonium ylides react with aromatic aldehydes to produce oxiranes,' olefins,por a mixture of both,3 depending upon the nature of substituent groups of the ylide and substrate molecule and on reaction conditions. In the case of semistabilized ylides derived from benzylarsonium salts, the distribution of products is largely determined by the electronic nature of the substituents on the ~ l i d e . ~ Moreover, the substituted oxirane or olefin invariably has the trans s t e r e ~ c h e m i s t r y . ~Benzylidene ,~ transfer from an optically active arsonium ylide to an aromatic aldehyde is therefore a potentially attractive route to optically active
trans-2,3-diaryloxiranes. Derivatives of readily available natural products are extremely attractive reagents for asymmetric synthesis. In this article we report the preparation of two epimeric tertiary arsines derived from (-)-menthol and their application to 2,3-diaryloxirane synthesis. The results are compared with those obtained by use of chiral arsonium ylides containing asymmetric arsenic atoms, a preliminary account of which has already been p u b l i ~ h e d . ~
Results and Discussion Synthesis. (+)-Diphenylneomenthylarsine(1) and (-) -Diphenylmenthylarsine (2). Nucleophilic displacement of chloride from (-)-menthyl chloride by the diphenylarsenide ion proceeds stereospecifically (with inversion of configuration) to produce (+)-diphenylneo(1)Henry, M. C.; Wittig, G. J. Am. Chem. SOC.1960,82,563.Allen,
D.W.; Jackson, G. J . Organomet. Chem. 1976,110,315.
(2)Johnson, A. W. J . Org. Chem. 1960,25, 183. Johnson, A. W.; Schubert, H. Ibid. 1978,35,2678.Lloyd, D.;Singer, M. I. C. Tetrahedron 1972,353. (3) Johnson, A. W.; Martin, J. 0. Chem. Ind. (London) 1965,1726. Gosney, I.; Lillie, T. J.; Lloyd, D. Angew Chem., I n t . E d . Engl. 1977,16, 487. (4)Trippett, S.; Walker, M. A. J. Chem. SOC. C 1971,1114. Kendurkar, P.S.; Tewari, R. S. J . Organomet. Chem. 1973,60,247.Kumari, N.; Kendurkar, P. S.;Tewari, R. S.Ibid. 1975,96,237. Kendurkar, P. S.;Tewari, R. S. Ibid. 1976,108,175. Tewari, R. S.;Chaturvedi, S. C. Indian J . Chem., Sect. B 1979,18B, 359. (5)Allen, D.G.; Roberts, N. K.; Wild, S. B. J . Chem. SOC.,Chem. Commun. 1978,346. (6)Still, W. C.;Novack, V. J. J . Am. Chem. SOC.1981, 103, 1283.
0276-7333/83/2302-0394$01.50/0
menthylarsine (I): mp 146-148 " c ; [&ID+69.6" (CHzCl2). The yield of the product was dependent upon the nature of the counterion associated with the arsenide ion. Use of [K(dioxane),][AsPh,] gave a 41% yield of the tertiary arsine, whereas the lithium and sodium salts led to 29 and 26.5% yields, respectively. Nevertheless, a reaction time of 60 h was required for the orange color of the potassium salt to be completely dissipated in boiling tetrahydrofuran. A lengthy reaction time was also found necessary for the preparation of the corresponding tertiary phosphine under similar conditions, and a marked dependence upon the counterion associated with the phosphide was n0ted.l
I 2 Quaternization of 1 with benzyl bromide in benzene a t 60 "C affords the epimeric benzylarsonium salt 3, ["ID +2.5O (CHzClZ).Reduction of this compound with lithium aluminium hydride produced (-)-diphenylmenthylarsine, 2, in almost quantitative yield, as a low melting solid (mp 52 'C), [&ID-79.6' (CH2C1,). The latter can be reconverted into 3 by treatment with benzyl bromide in benzene.
3 (7) Morrison, J. D.; Masler, W. F. J. Org. Chem. 1974,39,270.Aguiar, A. M.; Bahacca, N. S.; Burnett, R. E.; Masler, W. F.; Morrison, J. D.; Morrow, C. J. Ibid. 1976,41,1545.
0 1983 American Chemical Society
