Divergent Amine-Catalyzed [4 + 2] Annulation of Morita–Baylis–Hillman Allylic Acetates with Electron-Deficient Alkenes
作者:Silong Xu、Rongshun Chen、Zifeng Qin、Guiping Wu、Zhengjie He
DOI:10.1021/ol2032569
日期:2012.2.17
+ 2] annulation of Morita–Baylis–Hillman allylic acetates 2 with electron-deficientalkenes or diazenes has been developed for efficient syntheses of highly functionalized cyclohexenes, tetrahydropyridazines, and important spirocycles. This reaction unveils a new reactivity pattern of the intensely studied allyliccompounds 2 acting as a C4 synthon in Lewis base catalyzed annulationreactions and also
A convenient synthetic method for some functionalizedisoprenes employing 1-bromo-2-phenylthioethane and ethyl acetoacetate as starting materials is reported. It has also been found that the dienes thus obtained gave functionalized limonene analogs by Diels–Alder reaction with methyl vinyl ketone.
Preparation of Mikanecic Ester and its precursor, 1,3-butadiene-2-carboxylic ester
作者:L. K. Sydnes、L. Skattebøl、Christopher B. Chapleo、David G. Leppard、Karen L. Svanholt、André S. Dreiding
DOI:10.1002/hlca.19750580721
日期:1975.11.5
Eine thermische (a) und eine reduktive (b) Methode zur Herstellung von Mikanez-Estern wird beschrieben. Bei der ersten gelang der Nachweis des monomeren Vorläufers, 1,3-Butadien-2-carboxylester.
PBu<sub>3</sub>-Mediated Vinylogous Wittig Reaction of α-Methyl Allenoates with Aldehydes and Mechanistic Investigations
作者:Silong Xu、Rongshun Chen、Zhengjie He
DOI:10.1021/jo201466k
日期:2011.9.16
A highly stereoselective PBu3-mediated vinylogous Wittigolefination between α-methyl allenoates and a variety of aldehydes is presented as the first example of a practical and synthetically useful vinylogous Wittig reaction. Mechanistic experiments including deuterium-labeling, intermediate entrapment, and NMR monitoring have been deliberately conducted. On the basis of mechanistic investigations
First One-Pot Synthesis of Mikanecic Acid Derivatives from Allylic Phosphonates, via a Tandem-Sequence Horner-Wadworth-Emmons and Diels-Alder Reactions
作者:Hashim Al-Badri、Noël Collignon
DOI:10.1055/s-1999-3390
日期:1999.2
This paper describes a new, simple, general and efficient one-pot synthesis of mikanecic acid derivatives from allylic phosphonates, ethyl chloroformate and aqueous formaldehyde. The overall process involves a cascade sequence linking together metallation-alkoxycarbonylation, Horner-Wadworth-Emmons and Diels-Alder reactions.