Base-Induced Decarboxylation of Polyunsaturated<i>α</i>-Cyano Acids Derived from Malonic Acid: Synthesis of Sesquiterpene Nitriles and Aldehydes with<i>β</i>-,<i>φ</i>-, and<i>ψ</i>-End Groups
作者:Laurent Dufossé、Dominique Cartier、Benoist Valla、Mireille Fouillaud、Roger Labia、Alain Valla
DOI:10.1002/hlca.201200162
日期:2013.2
Catalytic base‐induced decarboxylation of polyunsaturated α‐cyano‐β‐methyl acids derived from malonic acid led to the corresponding nitriles 3 (Schemes 2 and 3), 6 (Scheme 5), and 9 (Scheme 6). This decarboxylation occurred with previous deconjugation of the α,β‐alkene moiety of the α‐cyano‐β‐methyl acid, leading to an α‐cyano‐β‐methylene propanoic acid which was easily decarboxylated (see Scheme 2)
丙二酸衍生的多不饱和α-氰基-β-甲基丙烯酸的催化碱诱导的脱羧反应生成相应的腈3(方案2和3),6(方案5)和9(方案6)。这种脱羧发生在先前α-氰基-β-甲基酸的α,β-烯烃部分发生共轭作用时,导致α-氰基-β-亚甲基丙酸易于脱羧(参见方案2)。β-在某些情况下,可以分离出亚甲基中间体;提出了机械途径。腈3、6和9分别还原为倍半萜醛4(β端基),7(Φ端基)和10(ψ端基)。