A concise total synthesis of biologically active frutinones via tributylphosphine-catalyzed tandem acyl transfer-cyclization
摘要:
A concise and step-economical total synthesis of biologically active frutinones has been achieved. Tributylphosphine (PBu3) efficiently induced the tandem acyl transfer-cyclization of carbonates 5 to afford 3-methoxycarbonylflavone derivatives 4 in excellent yields. Finally, concomitant deprotection and lactonization under acidic conditions furnished the desired frutinones A (1a), B (1b), and the proposed structure of frutinone C (1c). (C) 2014 Elsevier Ltd. All rights reserved.
Regioselectivity Influences in Platinum-Catalyzed Intramolecular Alkyne O–H and N–H Additions
作者:Jeff P. Costello、Eric M. Ferreira
DOI:10.1021/acs.orglett.9b03557
日期:2019.12.20
The steric and electronic drivers of regioselectivity in platinum-catalyzed intramolecular hydroalkoxylation are elucidated. A branch point is found that divides the process between 5-exo and 6-endo selective processes, and enol ethers can be accessed in good yields for both oxygen heterocycles. The main influence arises from an electronic effect, where the alkyne substituent induces a polarization
Benzofuran, benzothiophene or indole oligomers, co-oligomers, polymers and copolymers, methods for their production, and their use in charge transport and light emission regions of electroluminescent devices are described.
Benzofuran, benzothiophene or indole oligomers, co-oligomers, polymers and copolymers, methods for their production, and their use in charge transport and light emission regions of electroluminescent devices are described.