Formal Synthesis of Palmerolide A, Featuring Alkynogenic Fragmentation and syn-Selective Vinylogous Aldol Chemistry
摘要:
An enantioselective route to palmerolide A is described. The approach features original syntheses of three subunits, which are then assembled to produce a known late-stage intermediate and formally provide the highest overall yield of the natural product reported to date. Recent Innovations in alkynogenic fragmentation and vinylogous aldol methodology figure prominently In the synthesis of the C1-C15 and C16-C25 subunits, respectively.
Ring Opening of Cyclic Vinylogous Acyl Triflates Using Stabilized Carbanion Nucleophiles: Claisen Condensation Linked to Carbon−Carbon Bond Cleavage
作者:David M. Jones、Marilda P. Lisboa、Shin Kamijo、Gregory B. Dudley
DOI:10.1021/jo100249g
日期:2010.5.21
Addition of stabilized carbanionic nucleophiles to cyclic vinylogous acyl triflates (VATs) triggers a ring-opening fragmentation to give acyclic β-keto ester and related products, much like those observed traditionally in the Claisen condensation. Unlike in the classical Claisen condensation, however, the VAT-Claisen reaction described herein is rendered irreversible by C−C bond cleavage, not by deprotonation
Tandem Nucleophilic Addition/Fragmentation Reactions and Synthetic Versatility of Vinylogous Acyl Triflates
作者:Shin Kamijo、Gregory B. Dudley
DOI:10.1021/ja0608085
日期:2006.5.1
analysis of the chemistry of vinylogous acyl triflates provides insight into important chemical processes and opens new directions in synthetic technology. Tandem nucleophilic addition/C-C bond cleaving fragmentation reactions of cyclic vinylogous acyl triflates 1 yield a variety of acyclic acetylenic compounds. Full details are disclosed herein. A wide array of nucleophiles, such as organolithium and Grignard
Claisen-Type Condensation of Vinylogous Acyl Triflates
作者:Shin Kamijo、Gregory B. Dudley
DOI:10.1021/ol0527781
日期:2006.1.1
The Claisen-type condensation reaction of cyclic vinylogous carboxylic acid triflates with lithium enolates and their analogues produces acyclic alkynes bearing a 1,3-diketone-type moiety. The present transformation is proposed to proceed via a 1,2-addition of the enolate to the vinylogous acyl triflate, followed by fragmentation of the aldolate intermediate.
Novel anionic polycyclisation cascade. Highly stereocontrolled assembly of functionalised tetracycles akin to the middle core of the manzamines
作者:Laurent Turet、István E. Markó、Bernard Tinant、Jean-Paul Declercq、Rolland Touillaux
DOI:10.1016/s0040-4039(02)01463-6
日期:2002.9
Substituted gramines, in the presence of iotaBuOK, react with acrolein and beta-keto-phosphonates, via a novel sequence involving a multicomponent condensation followed by an anionic polycyclisation cascade, to afford in excellent overall yields, highly functionalised tetracyclic structures akin to the middle core of the manzamines. In this unique process, Lip to eight elementary transformations take place with remarkably high chemo- and stereocontrol. (C) 2002 Elsevier Science Ltd. All rights reserved.
Formal Synthesis of Palmerolide A, Featuring Alkynogenic Fragmentation and <i>syn</i>-Selective Vinylogous Aldol Chemistry
作者:Marilda P. Lisboa、David M. Jones、Gregory B. Dudley
DOI:10.1021/ol400014e
日期:2013.2.15
An enantioselective route to palmerolide A is described. The approach features original syntheses of three subunits, which are then assembled to produce a known late-stage intermediate and formally provide the highest overall yield of the natural product reported to date. Recent Innovations in alkynogenic fragmentation and vinylogous aldol methodology figure prominently In the synthesis of the C1-C15 and C16-C25 subunits, respectively.