芳基自由基环化反应：原小檗碱和罂粟碱类生物碱的一锅法合成

Aryl radical cyclizations: one-Pot syntheses of protoberberine and pavine alkaloids.

作者信息

Orito K, Satoh Y, Nishizawa H, Harada R, Tokuda M

机构信息

Laboratory of Organic Synthesis, Division of Molecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan.

出版信息

Org Lett. 2000 Aug 10;2(16):2535-7. doi: 10.1021/ol006213a.

DOI:10.1021/ol006213a

PMID:10956540

Abstract

Treatment of 2-(2'-bromo-beta-phenethyl)isocarbostyrils 7 with AIBN-Bu(3)SnH in boiling benzene gave 8-oxoberbines 3 in good yields. A similar treatment of 2-(2'-bromo-beta-phenethyl)isoquinolinium bromides 6 and their nor- and homoanalogues (10,11) induced 6-, 5-, and 7-exo radical closures in a one-pot manner to give protoberberines 2, dibenzo[b,g]indolizidine 14a and, dibenzo[a, h]-1-azabicyclo[5.4.0]undecane 15a, respectively. A one-pot radical cyclization of 1-(2'-bromobenzyl)isoquinoline methiodide 18a gave a pavine alkaloid, (+/-)-algemonine (19a).

摘要

在沸腾的苯中，用偶氮二异丁腈-三丁基氢化锡处理2-(2'-溴-β-苯乙基)异咔唑啉酮7，能以良好的产率得到8-氧代小檗碱3。对2-(2'-溴-β-苯乙基)异喹啉溴化物6及其去甲和高同系物(10,11)进行类似处理，能以一锅法诱导6-、5-和7-外向自由基环化反应，分别得到原小檗碱2、二苯并[b,g]吲哚里西啶14a和二苯并[a,h]-1-氮杂双环[5.4.0]十一烷15a。对1-(2'-溴苄基)异喹啉甲基碘化物18a进行一锅法自由基环化反应，得到一种罂粟碱生物碱，(±)-阿尔盖莫宁(19a)。