Dual Gold/Silver Catalysis: Indolizines from 2-Substituted Pyridine Derivatives via a Tandem C(sp<sup>3</sup>)–H Alkynylation/Iminoauration
作者:Chunyu Han、Yaowen Liu、Xianhai Tian、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1021/acs.orglett.1c03667
日期:2021.12.17
A dual gold/silver-catalyzed cascade C(sp3)–H alkynylation/iminoauration of 2-substituted pyridines with hypervalent iodine(III) reagents for the synthesis of indolizines is described. This novel reaction involves the formation of an alkynyl Au(III) species, a dual gold/silver-catalyzed C(sp3)–H functionalization, and a subsequent iminoauration process. A number of indolizines bearing diverse functionalities
The virtually quantitative, roomtemperature hydration of various terminal and internal alkynes in methanol/water requires between 0.01–0.05 mol% of [AuCl(NHC)] activated with 1.5 equiv. of silver triflate and 45 equiv. of triflic acid (both relative to gold complex) with ton of up to 300.000. Iptycenyl‐substituted NHC ligands play the key role and the most efficient NHC ligand is characterized by
Gold- and Silver-Catalyzed Reactions of Propargylic Alcohols in the Presence of Protic Additives
作者:Matthew N. Pennell、Peter G. Turner、Tom D. Sheppard
DOI:10.1002/chem.201102830
日期:2012.4.10
secondary and tertiary propargylicalcohols undergo a Meyer–Schusterrearrangement to give enones at room temperature in the presence of a gold(I) catalyst and small quantities of MeOH or 4‐methoxyphenylboronic acid. The syntheses of the enone natural products isoegomaketone and daphenone were achieved using this reaction as the key step. The rearrangement of primary propargylicalcohols can readily be combined
Synthesis of 3-substituted isoindolin-1-ones via a tandem desilylation, cross-coupling, hydroamidation sequence under aqueous phase-transfer conditions
作者:Socrates B. Munoz、Alexandra N. Aloia、Alexander K. Moore、Attila Papp、Thomas Mathew、Santos Fustero、George A. Olah、G. K. Surya Prakash
DOI:10.1039/c5ob02187a
日期:——
method for the synthesis of 3-methylene-isoindolin-1-ones 4 under aqueous phase-transfer conditions has been developed. Starting from 2-iodobenzamides 1 and (silyl)alkynes, the products are obtained in high yields and short reaction times (30 min) with the use of inexpensive CuCl/PPh3 catalyst system in the presence of n-Bu4NBr (TBAB) as a phase-transfer agent. Terminal alkynes are conveniently “unmasked”
Treatment of alkynes with o-methoxycarbonylphenylboronic acid in the presence of a cobalt catalyst resulted in the corresponding 2,3-disubstituted indenones.