A Direct Synthesis of Allenes by a Traceless Petasis Reaction
作者:Devon A. Mundal、Kelly E. Lutz、Regan J. Thomson
DOI:10.1021/ja301489n
日期:2012.4.4
A one-pot synthesis of allenes by the 2-nitrobenzenesulfonylhydrazide-mediated coupling of hydroxyaldehydes or ketones with alkynyl trifluoroborate salts is reported. This mild process involves in situ formation of a sulfonylhydrazone that reacts with alkynyl trifluoroborates to generate a transient propargylic hydrazide species. Decomposition of this unstable hydrazide via an intermediate monoalkyldiazine
Diene Synthesis by the Reductive Transposition of 1,2-Allenols
作者:Vincent J. Rinaolo、Emily E. Robinson、Abdallah B. Diagne、Scott E. Schaus、Regan J. Thomson
DOI:10.1055/s-0039-1690692
日期:2019.11
Monoalkyl diazene species are versatile intermediates that have enabled many useful synthetic transformations in complex chemical environments. Herein we report the reductive transposition of 1,2-allenols for the direct synthesis of dienes through an alkene walk process.
Defluorinative 1,3‐Dienylation of Fluoroalkyl <i>N</i>‐Triftosylhydrazones with Homoallenols
作者:Xiaolong Zhang、Jiahua Deng、Yong Ji、Rong Li、Paramasivam Sivaguru、Qingmin Song、Swastik Karmakar、Xihe Bi
DOI:10.1002/chem.202302562
日期:2023.12
Defluorinative 1,3-dienylation: A carbene strategy for the defluorinative 1,3-dienylation of fluoroalkyl N-triftosylhydrazones is reported. This method allowed for the preparation of α-fluoro-β-vinyl allyl ketones in high yield with excellent functional group tolerance.
to manzacidins A and D, here we report a highly efficient catalyticasymmetric α-allenylic alkylation reaction of NH2-unprotected aminoacid esters that is promoted by combined chiral aldehyde/palladium catalysis. Fifty examples of unnatural α,α-disubstituted aminoacid esters are reported with good-to-excellent yields and stereoselectivities. Based on this methodology, a key intermediate leading to
Enantioselective Synthesis of Allenes by Catalytic Traceless Petasis Reactions
作者:Yao Jiang、Abdallah B. Diagne、Regan J. Thomson、Scott E. Schaus
DOI:10.1021/jacs.6b11937
日期:2017.2.8
Allenes are useful functional groups in synthesis as a result of their inherent chemical properties and established reactivity patterns. One property of chemical bonding renders 1,3-substituted allenes chiral, making them attractive targets for asymmetric synthesis. While there are many enantioselective methods to synthesize chiral allenes from chiral starting materials, fewer methods exist to directly