作者:Jonathan W. Burton、Andrew B. Holmes、S. Y. Mak、Neil R. Curtis、Andrew N. Payne、Miles S. Congreve、Craig L. Francis
DOI:10.1055/s-2005-918470
日期:——
A synthesis of the halogenated medium-ring ether natural product (+)-obtusenyne is reported utilizing a Claisen rearrangement and an intramolecular hydrosilation as key steps.
报告利用克莱森重排和分子内水解作为关键步骤,合成了卤代中环醚天然产物(+)-obtusenyne。
Synthesis of (+)-Obtusenyne
作者:S. Y. Frankie Mak、Neil R. Curtis、Andrew N. Payne、Miles S. Congreve、Andrew J. Wildsmith、Craig L. Francis、John E. Davies、Sofia I. Pascu、Jonathan W. Burton、Andrew B. Holmes
DOI:10.1002/chem.200701567
日期:2008.3.17
An enantioselective synthesis of the halogenated medium-ring ether natural product (+)-obtusenyne is reported which uses the ring expansion of a seven-membered ketene acetal by means of a Claisen rearrangement to construct the core nine-membered oxygen heterocycle. The trans substituents across the ether linkage were established by using a transition-metal-catalyzed intramolecular hydrosilation reaction
Studies towards the synthesis of obtusenyne. A Claisen rearrangement approach to unsaturated nine-membered lactones.
作者:Neil R. Curtis、Andrew B. Holmes、Mark G. Looney
DOI:10.1016/s0040-4020(01)96169-1
日期:1991.8
An advanced intermediate for the synthesis of the Laurencia oxonane natural product obtusenyne 1. namely the unsaturated nine-membered lactone 3, was efficiently prepared in seven steps from (E)-3-hexenoic acid 7. The key transformation was the Claisen rearrangement of the vinyl keteneacetal 4, which represents novel methodology for the preparation of such unsaturated nine-membered lactones.
Regiochemical control of the ring opening of 1,2-Epoxides by means of chelating processes. 11. Ring opening reactions of aliphatic mono- and difunctionalized cis and trans 2,3- and 3,4-Epoxy Esters
The regiochemical outcome of the ring opening of 1,2-epoxides through chelation processes assisted by metal ions, was verified in the azidolysis of simple aliphatic cis and trans 2,3- and 3,4-epoxy esters and in the corresponding derivatives bearing an ether functionality (OBn) in an allylic relationship to the oxirane ring. The results indicate that the behavior of these epoxides is influenced both by the opening conditions (standard or metal-assisted) and the promoting metal salt [LiClO4 or Mg(ClO4)(2)].
Nucleophilic Ring-Opening of Epoxide and Aziridine Acetates for the Stereodivergent Synthesis of β-Hydroxy and β-Amino γ-Lactams
作者:Tula B. Bisol、Adailton J. Bortoluzzi、Marcus M. Sá
DOI:10.1021/jo102267h
日期:2011.2.4
A highlyregio- and stereoselective synthesis of novel β,γ-disubstituted γ-lactams with either an anti or syn relative configuration was developed from readily available epoxide and aziridine acetates. The key steps include the regio- and diastereocontrolled nucleophilic ring-opening of these three-membered heterocycles followed by mild reductive cyclization of the γ-azido ester intermediate. The method