ATOM TRANSFER ADDITION AND ANNULATION REACTIONS OF IODOMALONATES
ATOM TRANSFER ADDITION AND ANNULATION REACTIONS OF IODOMALONATES
复制标题
DOI：
10.1021/ja00206a016
复制
发表时间：
1989-11-22
影响因子：
15
通讯作者：
CHANG, CT
中科院分区：
文献类型：
--
作者：
CURRAN, DP;CHEN, MH;CHANG, CT
描述了碘丙二酸酯与烷基和苯基取代烯烃的原子转移加成和环化反应。例如，在10%的六丁基二锡存在下，甲基甲基丙二酸二甲酯和1-己烯在太阳光辐射下生成2-甲基-2-(2-碘己基)丙二酸二甲酯，产率为69%。在反应前用三丁基锡氢化物处理该反应混合物，可得到产率相当的2-甲基-2-己基丙二酸二甲酯。末端烯烃有很好的加合物产率，在许多情况下，除了-碘丙二酸盐和还原产物外，还可以生成内酯(分子内取代)和烯烃(消除HI)。当使用烯丙基或丙二醛时，环状产物在一步内形成。例如，在太阳灯下，10%六丁基二锡存在下，丙叉甲基丙二酸和1-己烯得到3，3-二甲氧基-L-(碘亚甲基)环戊烷，产率为52%。丙二酸酯和相关的1，3-二羰基化合物是有机合成中的中心官能团，因为它们可以通过经典的烷基化反应(丙二酸酯合成2)和现代的有机金属反应[Pd(0)促进的烯丙基烷基化反应3]快速组装在一起，而且它们很容易转化为其他官能团。我们最近发现，迄今鲜为人知的一类分子--碘-丙二酸盐很容易
Atom transfer addition and annulation reactions of iodomalonates with alkyl-and phenyl-substituted alkenes are described. For example, sunlampirradiation of dimethyl methyliodomalonate and 1-hexene in thepresence of 10% hexabutylditin provides dimethyl 2-methyl-2-(2-iodohexyl) malonate in 69% yield. Treatmentof this reaction mixture with tributyltin hydride prior to workup provides dimethyl 2-methyl-2-hexylmalonate in comparable yield. Good yields of adducts are observed with terminal alkenes, and inaddition to-iodomalonates and reduced products, lactones (resulting from intramolecular substitution) and alkenes (resulting from elimination of HI) can also be formed in many cases. When allyl-or progargyliodomalonates are used, annulated products are formed in a single step. For example, sunlamp irradiation of propargyliodomalonate and 1-hexene in the presence of 10% hexabutylditin provides 3, 3-dicarbomethoxy-l-(iodomethylene) cyclopentane in 52% yield. Mechanistic considerations that will allow thedesign of successful annulation reactions with electrophilic radicals like iodomalonates are presented.Malonates and related 1, 3-dicarbonyl compounds are central functional groups in organic synthesis because they are rapidly assembled by classical alkylation reactions (the malonic ester synthesis2) and modern organometallic reactions [Pd (0)-promoted allylic alkylations3], and because they are readily transformed into other functional groups. We have recently shown4 that iodo-malonates, a hitherto little-known class of molecules, 5 are readily