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Organic Synteses vol 70 - Meyers A.I.

Meyers A.I. , Boecman R.K. Organic Synteses vol 70 - John Wiley & Sons, 1992. - 163 p.
ISBN 0-471-57743
Download (direct link): organicsynthesesvol701992.pdf
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9. Crystallization of (R)-binaphthyl dipentanoate increases its enantiomeric purity from ~92% ee in the reaction mixture to >99% ee. The enantiomeric purity of the final product, binaphthol, is not increased by crystallization. The recrystallization step for the dipentanoate ensures high enantiomeric purity. Usually crystallization from methanol must be induced by scratching the side of the flask with a glass rod.
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The enantiomeric purity of the dipentanoate is determined after cleavage to binaphthol. A sample of dipentanoate is treated with an equivalent of sodium methoxide in methanol. After 30 min the solution is neutralized with excess acetic acid and analyzed by HPLC as in Note 8.
Waste Disposal Information
All toxic materials were disposed of in accordance with "Prudent Practices for Disposal of Chemicals from Laboratories”; National Academy Press; Washington, DC,
1983.
3. Discussion
Enantiomerically pure binaphthol is used as a chiral auxiliary.6 For example, it has been used to prepare chiral aluminum hydride reducing agents,7 chiral Lewis acids catalysts,8 and chiral crown ethers.9
The best previous resolution of binaphthol uses fractional crystallization of the diastereomeric cinchonine salts of binaphthol cyclic phosphate ester.10 The resolution using cholesterol esterase involves fewer manipulations and thus is simpler and faster than the cinchonine method. Fewer manipulations also enable the resolutions using cholesterol esterase to be carried out on a larger scale. The high enantioselectivity of cholesterol esterase assures high ee for the (S)-enantiomer, while crystallization of (R)-binaphthyl dipentanoate assures high enantiomeric purity for the (R)-enantiomer.
Octahydrobinaphthol and several spirobiindanols can also be resolved using this method, but several bromo-substituted binaphthols could not be resolved because their esters were not hydrolyzed.11
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1. Department of Chemistry, McGill University, 801 Sherbrooke St., W., Montreal, PQ H3A 2K6 Canada. Initial work was done at General Electric Company, Corporate Research and Development, Schenectady, NY.
2. Pummerer, R.; Prell, E.; Reiche, A. Ber. 1926, 59B, 2159; note correction in Note 12 of Reiche, A.; Jungholt, K.; Frühwald, E. Ber. 1931, 64B, 578.
3. Irochijima, S.; Kojima, N. Agric. Biol. Cham. 1980, 46, 1593.
4. Pirkle, W. H.; Schreiner, J. L. J. Org. Chem. 1981, 46, 4988.
5. Okamoto, Y.; Honda, S.; Okamoto, I.; Yuki, H. J. Am. Chem. Soc. 1981, 103, 6971.
6. Review (in Japanese): Miyano, S.; Hashimoto, H. Yuki Gosei Kagaku Kyokaishi 1986, 44, 713; Chem. Abstr. 106, 137988e.
7. Noyori, R.; Tomino, I.; Tanimoto, Y.; Nishizawa, M. J. Am. Chem. Soc. 1984,
106, 6709; Noyori, R.; Tomino, I.; Yamada,. M.; Nishizawa, M. J. Am. Chem. Soc.
1984, 106, 6717.
8. Sakane, S.; Maruoka, K.; Yamamoto, H. Tetrahedron Lett. 1985, 26, 5535; Maruoka, K.; Itoh, T.; Shirasaka, T.; Yamamoto, H. J. Am. Chem. Soc. 1988, 110, 310.
9. Sogah, G. D. Y.; Cram, D. J. J. Am. Chem. Soc. 1979, 101, 3035.
10. Jacques, J.; Fouquey, C. Org. Synth. 1989, 67, 1; Truesdale, L. K. Org. Synth. 1989, 67, 13; Kyba, E. P.; Gokel, G. W.; de Jong, F.; Koga, K.; Sousa, L. R.; Siegel, M. G.; Kaplan, L.; Sogah, G. D. Y.; Cram, D. J. J. Org. Chem. 1977, 42, 4173.
11. Kazlauskas, R. J. J. Am. Chem. Soc. 1989, 111, 4953.
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Appendix
Chemical Abstracts Nomenclature (Collective Index Number); (Registry Number)
(S)-(-)-1,1'-Bi-2-naphthol: [і,і'-ВіпарйіаІепе]-2,2ЧІюІ, (S)-(-)- (8);
[1,1'-Binaphthalene]-2,2'-diol, (S)- (9); (18531-99-2)
(R)-(+)-1,1'-Bi-2-naphthol: [1,1'-Binaphthalene]-2,2'-diol, (R)-(+)- (8); [1,1'-Binaphthalene]-2,2’-diol, (R)- (9); (18531-94-7)
(±)-1,1’-Bi-2-naphthyl pentanoate: Pentanoic acid, [1,1'-binaphthalene]-2,2'-diyl ester, (±)- (12); (100465-51-8)
(±)-Bi-2-naphthol: [1,1'-Binaphthalene]-2,2'-diol, (+)- (9); (41024-90-2)
Pentanoyl chloride (8,9); (638-29-9)
(R)-1,1'-Bi-2-naphthyl pentanote: Pentanoic acid, [1,1'-binaphthalene]-2,2'-diyl ester, (R)- (12); (110902-38-0)
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3,4-DIETHYLPYRROLE AND 2,3,7,8,12,13,17,18-OCTAETHYLPORPHYRIN (21H,23H-Porphine, 2,3,7,8,12,13,17,18-octaethyl-)
B.
+ o2n
+ AcoO
C. 2 + C=NCH2C02Et
NaOH/(CH2OH)2
THF/IPA H'^^N,^C02Et 190°C /30 min
: XT
N
H
4
D. 4 + CH20(
<aq)
1) C6H6/p-TsOH/reflux
2)Oz
Submitted by Jonathan L Sessler,1 Azadeh Mozaffari, and Martin R. Johnson. Checked by Jurgen Fischer and Ekkehard Winterfeldt.
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1. Procedure
A. 4-Nitro-3-hexanol (I).2 To a 2-L, three-necked, round-bottomed flask equipped with a mechanical stirrer, thermometer, dropping funnel, and drying tube are added propionaldehyde (174 g, 3 mol) and isopropyl alcohol (IPA) (450 mL) (Note 1). The solution is stirred while finely ground potassium fluoride (25 g, 0.15 mol) is added to the flask. 1-Nitropropane (267.3 g, 3 mol) (Note 1) is then added dropwise with stirring, and the temperature is kept below 40°C with the aid of an ice bath (Note 2). The ice bath is removed about 30 min after the addition of 1-nitropropane is complete. The flask contents are stirred for an additional 18 hr. The catalyst is then removed by filtration and the filtrate is concentrated under reduced pressure. The residue is poured into water (500 mL) and the oil is extracted with ether (3 x 300 mL). The ethereal layer is dried over anhydrous sodium sulfate (NagSC),*), and the solvent is removed under reduced pressure. The remaining liquid is distilled under reduced pressure and the fraction boiling at 88-90°C/2 mm is collected in a tared, 1-L round-bottomed flask, yielding 3-nitro-4-hexanol (330 g, 2.24 mol, 65%) (Note 3). The flask containing the product is used directly in the next step.
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