3-乙酰氧基-1-(4-氨基烷基)环己烯的钯(0)催化环化提供了对在组织毒素中发现的1-azaspiro [5.5]十一烷环系统的便捷访问。7-丁基衍生物(4; R 1 = Bu n,R 2 = H)的氢硼化和纯化的硼烷加合物与三甲基氧化胺的氧化提供了N-苄基脱戊基过氢组氨酸毒素,其易于通过氢解转化为(±)-去戊基过氢组氨酸毒素。超过钯碳。
Palladium-Catalyzed Cascade Arylation of Vinylogous Esters Enabled by Tris(1-adamantyl)phosphine
作者:Yi-Chi Yang、Yi-Ching Lin、Yen-Ku Wu
DOI:10.1021/acs.orglett.9b03071
日期:2019.12.6
Described is a method for the transformation of a cyclic vinylogousester to the corresponding polyarylated product. We found a catalytic system comprising palladium diacetate and tris(1-adamantyl)phosphine is quite effective in promoting a set of controlled cascade arylations. As a result, a range of novel (hetero)aryl-containing scaffolds was synthesized with a high level of efficiency.
A method is presented for the synthesis of diaryl cyclic vinylogousesters. The sequence of C(sp3)–H arylation events is programed under the differentiated reactivity of the aryl halides, and the optimized reaction system is effectively diverted from producing dihomo-arylated products. The site selectivity of the second arylation is notably modulated by the substitution pattern of the substrates.