STEREOSELECTIVE SYNTHESES OF ERYTHRO-BETA-AMINO AND THREO-BETA-AMINO ALCOHOL DERIVATIVES VIA HETERO-DIELS-ALDER REACTIONS
STEREOSELECTIVE SYNTHESES OF ERYTHRO-BETA-AMINO AND THREO-BETA-AMINO ALCOHOL DERIVATIVES VIA HETERO-DIELS-ALDER REACTIONS
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DOI：
10.1021/ja00194a033
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发表时间：
1989-06-07
影响因子：
15
通讯作者：
AFONSO, MM
中科院分区：
文献类型：
--
作者：
MIDLAND, MM;AFONSO, MM
研究了1,3-二甲氧基-1-[(三甲基甲硅烷基)氧基]丁二烯与多种N-保护的α-氨基醛在路易斯酸的影响下的反应。该反应提供了可用于进一步转化的α，β-不饱和内酯。当N-叔丁氧基羰基保护的氨基醛与二乙基氯化铝或三-[3-[(七氟丙基)羟亚甲基]樟脑根]铕(III)一起使用时，反应提供与螯合控制过程一致的非对映异构体。非对映比范围为 80:20（丙醛）至 95:5（缬醛）。当使用 N,N-二苄基保护的胺醛时，这种立体化学会急剧逆转。非对映体比率始终为 99:1，有利于 Cram 型产品。
The reaction of 1,3-dimethoxy-1-[(trimethylsilyl)oxy]butadiene with a variety of N-protected .alpha.-amino aldehydes under the influence of Lewis acid has been studied. The reaction provides an .alpha.,.beta.-unsaturated lactone that is useful in further transformations. When N-tert-butoxycarbonyl-protected amino aldehydes are used with diethylaluminum chloride or tris-[3-[(heptafluoropropyl)hydroxymethylene]camphorato]europium(III) as a catalyst, the reaction provides a diastereomer consistant with a chelation-controlled process. Diastereometric ratios range from 80:20 (alaninal) to 95:5 (valinal). This stereochemistry is dramatically reversed when N,N-dibenzyl-protected amine aldehydes are used. Diastereomeric ratios are consistently 99:1 in favor of the Cram-type product.