Unsaturated Nitriles: Precursors for a Domino Ozonolysis−Aldol Synthesis of Oxonitriles
作者:Fraser F. Fleming、Adrian Huang、Vaqar A. Sharief、Yifang Pu
DOI:10.1021/jo9822885
日期:1999.4.1
five-membered oxonitriles 22a-c are prepared by analogous ozonolysis-aldol cyclizations employing omega-alkenyl beta-ketonitriles. The method tolerates various substitution patterns and allows for the synthesis of beta,beta-disubstituted oxonitriles (22c). The reaction conditions are essentially neutral providing the beta-hydroxyoxonitriles 22d and 22e with only trace amounts of the aromatic dehydration
通过串联的臭氧分解-醛醇缩合序列制备环状的五元,六元和七元乙腈。环戊烯基乙腈(4)和环己烯基乙腈(12)通过高效的一锅合成法分别提供了扩环的乙腈3(98%)和17(58%)。通过使用ω-烯基β-酮腈的类似的臭氧分解-醛醇缩合环化来制备同源的五元氧腈22a-c。该方法耐受各种取代模式,并允许合成β,β-二取代的乙腈(22c)。反应条件基本上是中性的,仅向β-羟基氧腈22d和22e提供痕量的芳族脱水产物。