Highly Z-selective synthesis of α,β-unsaturated nitriles using the Horner–Wadsworth–Emmons reaction
作者:Kaori Ando、Miho Okumura、Shigeo Nagaya
DOI:10.1016/j.tetlet.2013.02.020
日期:2013.4
A new HWE reagent, (o-tBuC6H4O)2P(O)CH2CN (2e), reacts with various types of aldehydes to give Z-α,β-unsaturatednitriles with 86% to >99% Z-selectivity. Especially, the reaction of 2e with bulkier aldehydes, both aromatic and aliphatic, gave the Z-olefins with extremely high selectivity. The combination of t-BuOK and 18-crown-6 (1 equiv) is the base of choice for aromatic aldehydes and t-BuOK is generally
一种新的HWE试剂(o - t BuC 6 H 4 O)2 P(O)CH 2 CN(2e)与各种类型的醛反应生成Z -α,β-不饱和腈,含量为86%至> 99%Z选择性。特别地,2e与较大的醛(芳族和脂族)的反应使Z-烯烃具有极高的选择性。的组合吨-BuOK和18-冠-6(1当量)是选择用于芳族醛的基极和吨-BuOK通常是选择用于脂族醛的碱。
Exploiting domino enyne metathesis mechanisms for skeletal diversity generation
作者:Richard J. Spandl、Hèléne Rudyk、David R. Spring
DOI:10.1039/b807278g
日期:——
In the context of diversity-oriented synthesis, the exploration and optimization of the dominometathesis of decorated norbornenes allowed complex polycyclic architectures to be generated in a highly efficient and atom-economical process.
The Stereochemical Course of Intramolecular Michael Reactions
作者:Eugene E. Kwan、Jonathan R. Scheerer、David A. Evans
DOI:10.1021/jo302138z
日期:2013.1.4
We present a general model for understanding the stereochemicalcourse of intramolecular Michael reactions. We show that the addition of β-ketoester enolates to α,β-unsaturated esters and imides bearing adjacent stereocenters (X, Y = H, Me, OR) leads to high levels of asymmetric induction. Reinforcing and nonreinforcing stereochemical relationships are evaluated from the syn and anti reactant diastereomers
A Regio- and Diastereoselective Intramolecular Nitrone Cycloaddition for Practical 3- and 2,3-Disubstituted Piperidine Synthesis from γ-Butyrolactone
作者:Benjamin E. Stephens、Fei Liu
DOI:10.1021/jo8018285
日期:2009.1.2
3-disubstituted piperidines, featuring an intramolecular nitronecycloaddition with high regio- and diastereoselectivity, was achieved in six steps and 36−66% overall yield from commercially available γ-butyrolactone or 1,4-butanediol. A new N-alkenyl nitrone enoate was used in this intramolecular nitronecycloaddition, and the regioselectivity, diastereoselectivity, and reversibility of this cycloaddition were
Sequential C sp 3H Arylation and Olefination: Total Synthesis of the Proposed Structure of Pipercyclobutanamide A
作者:Will R. Gutekunst、Ryan Gianatassio、Phil S. Baran
DOI:10.1002/anie.201203897
日期:2012.7.23
square: A strategy for assembling tetrasubstituted cyclobutanes is reported in the context of a short, protecting‐group‐free synthesis of the proposedstructure of pipercyclobutanamide A. The route features sequentialCH functionalizations on an unactivated cyclobutane wherein CC bonds to aryl and styryl groups are made one by one in a stereocontrolled fashion. DG=directing group.
Hip to be square:在一个短的、无保护基团合成哌环丁酰胺 A 结构的背景下,报道了一种组装四取代环丁烷的策略。该路线的特点是在未活化的环丁烷上连续 C  H 官能化,其中 C  C与芳基和苯乙烯基的键以立体控制的方式一个接一个地形成。DG=指导组。