Polyfunctional, Structurally Defined Catalysts for the Enantioselective Addition of Dialkylzine Reagents to Aldehydes

Journal of Organic Chemistry

Volumn 55, Issue 3, 1990, Pages 784-786

  Corey, E J ^a   Yuen, Po Wai ^a   Hanon, Francis J ^a   Wierda, Derk A ^a  

^a HARVARD UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ALDEHYDE DERIVATIVE; ZINC COMPLEX;

ARTICLE; CHEMICAL REACTION; DRUG STRUCTURE; DRUG SYNTHESIS; METHODOLOGY; NONHUMAN;

EID: 0025317376     PISSN: 00223263     EISSN: 15206904     Source Type: Journal    
DOI: 10.1021/jo00290a002     Document Type: Article

References (22)

1. Oguni, N.; Omi, T. Tetrahedron Lett. 1984, 25, 2823–2824.
2. See also: Oguni, N.; Omi, T.; Yamamoto, Y.; Nakamura, A. Chem. Lett. 1983, 841–842.
3. Kitamura, M.; Suga, S.; Kawai, K.; Noyori, R. J. Am. Chem. Soc. 1986, 108, 6071–6072.
4. Soai, K.; Ookawa, A.; Ogawa, K.; Kaba, T. J. Chem. Soc., Chem. Commun. 1987, 467–468.
5. Itsuno, S.; Frechet, J. M. J. J. Org. Chem. 1987, 52, 4140–4142.
6. Yoshioka, M.; Kawakita, T.; Ohno, M. Tetrahedron Lett. 1989, 30, 1657–1660.
7. Soai, K.; Niwa, S.; Yamada, Y.; Inoue, H. Tetrahedron Lett. 1987, 28, 4841–4842.
8. Smaardijk, A. A.; Wynberg, H. J. Org. Chem. 1987, 52, 135–137.
9. Noyori, R. Chem. Soc. Rev. 1989, 18, 187–208.
10. For previous results from this laboratory, see: Corey, E. J.; Han-non, F. J. Tetrahedron Lett. 1987, 28, 5233-5233- 1987, 28, 5237–5240.
11. Corey, E. J. Proceedings of the 31st National Organic Symposium of the American Chemical Society, June 1989, pp 1–14.
12. Corey, E. J. The Chemist 1989, July/August 3–5.
13. Corey, E. J.; Im-winkelried, R.; Pikul, S.; Xiang, Y. B. J. Am. Chem. Soc. 1989, 111, 5493–5495.
14. Of course, such chemical catalysts, while similar to enzymes in the above-named actions, lack the size- and shape-selecting binding sites of the much larger enzymic molecules.
15. Rigo, B.; Lespagnol, C.; Pauly, M. J. Heterocycl. Chem. 1988, 25, 49–57.
16. Asher, V.; Becu, C.; Anteunis, M. J. O.; Callens, R. Tetrahedron Lett. 1981, 22, 141–144.
17. The following peaks were observed in the 1H NMR spectrum of 9 (500 MHz, C6D6): 6 7.89 (b, 1 H, Ar), 7.53 (d, J7.53 Hz, 1 H, Ar), 7.23 (m, 4 H, Ar), 7.07 (m, 4 H, Ar), 4.11 (ddd, 1 H, J7.50, 9.80, 10.1 Hz, NCHCPh2OZn), 2.49 (m, 1 H, NCHCH2N(CH3)2), 2.42 (dd, J12.5, 12.4 Hz, 1 H, (CH3)2NCH2), 1.86 (br s, 6 H, (CH3)2N), 1.64 (b, 1 H, NH), 1.32 (m, 1 H, pyrrolidine ring H), 1.18 (t, 5 H, ZnCH2CH3 + 1 pyrrolidine ring H + 1 (CH3)2NCH2), 1.08 (m, 1 H, pyrrolidine ring H), 0.96(m, 1 H, pyrrolidine ring H), -0.03 (m, 2 H, ZnCH2CH3).
18. Empirical formula C22H30O2N2ZN2, monoclinic, space group P21, a 9.168 (5) A, b 10.392 (5) A, c 10.596 (6) A, 0 104.69(5), Z 2, V 1003 A, Dc 1.34 g -, X 0.71073 A. Structure solved by direct methods (SHELTX-PLUS), R(F) 0.0699, Rw(F) 0.0708 for 4257 total reflections, 2627 with F0 6.00r(Fo). Largest A /a for last cycle of refinement 0.004. We are indebted to Jonathan Zerkowski for the collection of data for the X-ray study.
19. The rotation of the (S)-(-)- 1-phenylpropanol isolated in 94 yield from a typical experiment was [c]23D -42.2 (c 0.95, CHC13); the enantiomeric purity was determined to be 95 ee by conversion to the menthyloxycarbonyl derivative (1-phenylpropanol, (-)-menthylchloro-formate, DMAP, and pyridine in CH2C12), followed by capillary gas chromatographic analysis (DB1-30W column, 200 C oven temperature; retention time of the major diastereomer, 9.43 min; minor diastereomer, 9.83 min)
20. (See: Westley, J. W.; Halpern, B. J. Org. Chem. 1968, 33, 3978–3980). The same enantiomeric purity was also determined by HPLC analysis of the alcohol (Bakerbond DNBPG-ionic column, 0.25% 2-propanol in hexanes, 1.5 mL/min, 750 psi, 254 nm detector; retention time of (S)-(-)-l-phenylpropanol, 15.16 min; (/?)-(+)-l-phenylpropanol, 15.87 min).
21. It is also possible that the lower enantioselectivity with p-meth-oxybenzaldehyde may be partly the result of other competing pathways such as one involving coordination of the aldehyde at the acyclic O-Zn-Et subunit in 9 and adduct formation directly from this structure. The exchange of the dimethylamino ligand for the OZnEt ligand at the central zinc of 10 is another possible source of lower stereoselectivity. Piv-aldehyde which also reacts slowly with diethylzinc and 10 mol of 7 (17 conversion after 60 h at 23 C) also reacts with lowered enantioselectivity (69 ee).
22. This research was assisted financially by grants from the National Science Foundation and the National Institutes of Health.