Arenediazonium o-benzenedisulfonimides can be used as new and efficient reagents for Heck-type arylation reactions of some common substrates containing C–C multiple bonds, namely ethyl acrylate, acrylic acid, acroleyne, styrene and cyclopentene. The reactions were carried out in an organic solvent, in the presence of Pd(OAc)2 as pre-catalyst, and gave rise to arylated products, for example, ethyl cinnamates
Gold catalyzed Heck-coupling of arenediazonium <i>o</i>-benzenedisulfonimides
作者:Margherita Barbero、Stefano Dughera
DOI:10.1039/c7ob02624b
日期:——
Diazonium salts, and precisely arenediazonium o-benzenedisulfonimides, have been used for the first time as efficient electrophilic partners in gold catalyzed Heck-coupling reactions. The synthetic protocol was general, easy and gave the target products in satisfactory yields. Mechanistic insights revealed the fundamental roles of the o-benzenedisulfonimide anion as an electron transfer agent thath promotes
Step saver: Carbonyl groups with lower reactivities can be transformed in the presence of more reactive ones by treatment with PPh3 (or PEt3) and TMSOTf prior to the reaction (see scheme; TMS=trimethylsilyl, Tf=trifluoromethanesulfonyl). This methodology can be applied to reduction and alkylation reactions, and enabled the short asymmetric totalsynthesis of (+)‐centrolobine with the highest overall
Reaction of diazonium salts with transition metals—III
作者:K. Kikukawa、K. Nagira、F. Wada、T. Matsuda
DOI:10.1016/s0040-4020(01)97711-7
日期:1981.1
Palladium (0) catalyzed reactions of arenediazonium salts for arylation of aliphatic and cyclic olefins and allylic alcohols, styrene and ethyl acrylate were studied. Effects of the olefinic compounds and other reaction variables on the arylation were presented. Arylpalladiumspecies was proposed as the most plausible intermediated in this reaction.
Bioinspired Metal‐Free Formal Decarbonylation of α‐Branched Aliphatic Aldehydes at Ambient Temperature
作者:Sven C. Richter、Martin Oestreich
DOI:10.1002/chem.201902082
日期:2019.6.26
secondary aliphatic aldehydes. The new methodology mimics the biosynthetic decarbonylation pathway through oxidative C−C bondcleavage rather than the C(O)−Hbond activation known from conventional Tsuji–Wilkinson‐type reactions. The substrate scope is complementary to existing transition‐metal‐catalyzed protocols.