Novel Cashmeran odorants were designed by molecular modeling. Their short syntheses involve a novel asymmetric Brønsted acid catalyzed Michael addition of unactivated α‐substituted ketones. This key transformation was realized by utilizing a new type of enol activation catalysis and affords different cyclic ketones bearing α‐quaternary stereocenters in good to excellent yields and with high enantioselectivity. Subsequent McMurry coupling and Saegusa–Ito oxidation furnished the enantiopure target odorants, one enantiomer of which indeed possesses the typical olfactory aspects of Cashmeran.

中文翻译：

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“烯醇催化”法设计Cashmeran气味的对映体和对映选择性合成

通过分子模型设计了新颖的Cashmeran增香剂。他们的简短合成涉及一种新的不对称布朗斯台德酸催化未活化的α-取代的酮的迈克尔加成反应。这种关键的转变是通过利用新型的烯醇活化催化来实现的，并提供了具有α-季立体中心的不同环状酮，产率高至优异，对映选择性高。随后的McMurry偶联和Saegusa-Ito氧化提供了对映纯目标气味，其中一种对映异构体确实具有Cashmeran的典型嗅觉特性。