Addition of Alkynes to Aldehydes and Activated Ketones Catalyzed by Rhodium−Phosphine Complexes
作者:Pawan K. Dhondi、Patrick Carberry、Lydia B. Choi、John D. Chisholm
DOI:10.1021/jo701643h
日期:2007.12.1
A mixture of 2-(di-tert-butylphosphino)biphenyl and dicarbonylacetonato rhodium(I) provides an effective catalyst system for the addition of alkynes to aldehydes and activated ketones. In contrast to the more common zinc-catalyzed processes, enolizable 1,2-dicarbonyls are excellent substrates for these rhodium-catalyzed additions. This reaction allows for the formation of propargylic alcohols under
Ivorenolide A (1), a novel 18-membered macrolide featuring conjugated acetylenic bonds and five chiral centers, was isolated fromKhayaivorensis. The structure of 1 was fully determined by spectroscopic analysis, single-crystal X-ray diffraction, and bioinspired total synthesis. Both compound 1 and its synthetic enantiomer 2 showed potent and selective immunosuppressive activity.
Total Synthesis and Structure Revision of Diplobifuranylone B
作者:Xinpeng Cheng、Carlos D. Quintanilla、Liming Zhang
DOI:10.1021/acs.joc.9b01613
日期:2019.9.6
An asymmetric total synthesis of diplobifuranylone B was achieved in 10 steps for the longest linear sequence and in 15.8% overall yield from commercially available methyl (R)-(+)-lactate and l-glutamic acid. This synthesis features a stereoselective construction of the key 2,5-dihydrofuran ring in the natural product via a recently developed asymmetric gold catalysis. The stereochemical flexibility
Total Synthesis of the Allenic Macrolide (+)-Archangiumide
作者:Jack L. Sutro、Alois Fürstner
DOI:10.1021/jacs.3c13304
日期:2024.1.31
gains a strategic role beyond its mere safeguarding function. Although the gold catalyzed reaction per se is stereoablative, the macrocyclic frame of the target was found to impose high selectivity and a stereoconvergent character on the transformation. The required substrate was formed by ring closing alkyne metathesis (RCAM) with the aid of a new air-stable molybdenum alkylidyne catalyst.