面包酵母作为生物催化剂潜手性的酮构建手性中心的反应，近几年在中得到广泛的应用。最初面包酵母的应用是1898年将糠醛还原为糠醇，之后经Macleod和Hub的研究拓宽了这一反应的应用。近几十年对于此反应在水相进而在有机相中反应取得进展，越来越多的有机合成家考虑应用酵母还原反应底物制备重要的手性。
酵母还原有以下特点：高度专一的立体选择性；反应温和反应速率快；还原反应收率高，成本低；符合绿色化学要求，环境友好。
反应应用
合成芬氟拉明的重要中间体(J. Org. Chem. 1991,56,6019)：
托莫西汀类似物的手性中心构建(Indian J. Chem. 1992,31B, 803)：
j酵母还原 Ethyl Acetoacetate: (S)-( + )-Ethyl 3-Hydroxytanoate ( Organic Syntheses, Coll.Vol. 7, p.5; Vol. 63, p.1):
A 4-L,three-necked, round-bottomed flask equipped with mechanicalstirrer, bubble counter, and a stopper is charged with 1.6 L tap water, 300 g of sucrose,and 200 g of baker's yeast, which are added with stirring in this order. Themixture is stirred for 1 hr at about 30°C, 20.0 g (0.154mol) of ethylacetoacetate is added, and the fermenting suspension is stirred for another 24 hr at roomtemperature. A warm (ca. 40°C) solution of 200 g of sucrose in 1 Lof tap water is then added, followed 1 hr later by an al 20.0 g (0.154 mol) of ethylacetoacetate. Stirring is continued for 50–60 hr at roomtemperature. When the is complete by gas chromatographic analysis, themixture is worked up by first adding 80 g of Celite and filtering through a sintered-glass funnel (porosity 4, 17-cm diam). Afterthe filtrate is washed with 200 mL of water, it is saturated with sodium and extracted with five 500-mL portions of ethylether. The combined etherextracts are dried over magnesiumsulfate, filtered, and concentrated with a rotaryevaporator at 35°C bath temperature to a volume of 50–80 mL. Thisresidue is fractionally distilled at a pressure of 12 mm through a cm Vigreux column, and the fraction boiling at 71–73°C (12 mm) is collected to give 24–31 g (59–76%) of (S)-( + )-ethyl 3-hydroxybutanoate; thespecific rotation [α]25D + 37.2° (chloroform,c 1.3) corresponds to an enantiomeric excess of 85%.
The enantiomeric excessmay be enhanced by several crystallizations of the 3,5-dinitrobenzoatederivative or else by using "starved" yeast.
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