Formation of trans ring-fused compounds by an alkylation-radical cyclization sequence
摘要:
Enolates derived from bicyclic lactones of type 1 (Scheme I) can be alkylated with 2-propynylic halides to give products 2, in which the unsaturated alkyl group is syn to the adjacent ring-fusion hydrogen. Reaction of 2 with sodium phenyl selenide and then with diazomethane produces esters 3, and these give trans ring-fused bicyclic compounds 4 when treated with triphenyltin hydride in the presence of a radical initiator. The bicyclic compounds afford ketones on double-bond cleavage, and the angular ester function can be converted into a methyl group. Similar processes occur if an aldehyde is used in the first step instead of a halide. The methodology is general.
Reactions of 1,2-dehydropyrrolidin-5-one with 1,3-dienes. Synthesis of <i>dl</i>-gephyrotoxin 223AB
作者:Oliver E. Edwards、Austin M. Greaves、Wing-Wah Sy
DOI:10.1139/v88-191
日期:1988.5.1
Evidence is presented that the regiospecific and often stereospecific pseudo-Diels–Alder reactions of 1,3-dienes with N-acyl immonium salts, derived from 5-ethoxy-2-pyrrolidinone, are stepwise reactions. 6,7-Dehydroindolizidinones, unsaturated lactam esters, and new indene and furan derivatives are described. A synthesis of dl-gephyrotoxin 223AB (indolizidine 223AB) from trans-1,3-heptadiene was achieved
Herein, we report the redox‐neutral, intermolecular, and highly branch‐selectiveamidation of allylicC−H bonds enabled by Cp*IrIII catalysis. A variety of readily available carboxylic acids were converted into the corresponding dioxazolones and efficiently coupled with terminal and internal olefins in high yields and selectivities. Mechanistic investigations support the formation of a nucleophilic
在本文中,我们报道了由Cp * Ir III催化实现的烯丙基CH键的氧化还原中性,分子间和高度分支选择性酰胺化。将各种容易获得的羧酸转化为相应的二恶唑酮,并以高收率和选择性将其与末端和内部烯烃有效偶联。机理研究支持亲核性Ir III-烯丙基中间体的形成,而不是将Ir-nitrenoid物种直接插入烯丙基CH键中。
Regiocontrolled Reductive Vinylation of Aliphatic 1,3-Dienes with Vinyl Triflates by Nickel Catalysis
作者:Xiaobo Pang、Zhen-Zhen Zhao、Xiao-Xue Wei、Liangliang Qi、Guang-Li Xu、Jicheng Duan、Xue-Yuan Liu、Xing-Zhong Shu
DOI:10.1021/jacs.1c00142
日期:2021.3.31
a powerful tool for divergent synthesis, yet it remains a long-standing challenge for aliphatic substrates. Herein, we report a reductive approach for a branch-selective 1,2-hydrovinylation of aliphatic 1,3-dienes with R–X electrophiles, which represents a new selectivity pattern for diene functionalization. Simple butadiene, aromatic 1,3-dienes, and highlyconjugated polyene were also tolerated. The
Diamination of Conjugated Dienes and Trienes Catalyzed by <i>N</i>-Heterocyclic Carbene−Pd(0) Complexes
作者:Liang Xu、Haifeng Du、Yian Shi
DOI:10.1021/jo0709394
日期:2007.8.31
This paper describes a diamination process using di-t-butyldiaziridinone as nitrogen source and N-heterocyclic carbene−Pd(0) complex as catalyst. A wide variety of conjugated dienes and trienes can be effectively diaminated in good yields with high regio- and stereoselectivities.
Catalytic Asymmetric Synthesis of Cyclic Sulfamides from Conjugated Dienes
作者:Richard G. Cornwall、Baoguo Zhao、Yian Shi
DOI:10.1021/ol303469a
日期:2013.2.15
This paper describes the catalytic asymmetric diamination of alkyl dienesusing N,N′-di-tert-butylthiadiaziridine 1,1-dioxide in the presence of Pd(0) and a chiral phosphoramidite ligand to give cyclic sulfamides in high yield and high ee. The diamination is also amenable to gram scale.
本文描述了在 Pd(0) 和手性亚磷酰胺配体存在下使用N , N '-二叔丁基噻二氮丙啶 1,1-二氧化物催化不对称二烯二胺化,以高产率和高 ee 得到环状磺酰胺。该二胺化也适合克级规模。