Reversal of Selectivity in Gold-Catalyzed Cyclizations of 3,3-Disubstituted 1,4-Diynes
摘要:
A general synthetic access to 3,3-disubstituted 1,4-diynes bearing a quaternary carbon center from acetylacetone was developed. The compounds were cyclized to the corresponding enol ethers by cationic gold complexes. The reactions occur in complete exo-selectivity in contrast to compounds incorporating an alkoxy substituent in the 3-position. A mechanistic rationale for this reversal of selectivity is provided.
An Efficient and Mild CuI/<scp>l</scp>-Proline-Catalyzed Arylation of Acetylacetone or Ethyl Cyanoacetate
作者:Yongwen Jiang、Nan Wu、Haihong Wu、Mingyuan He
DOI:10.1055/s-2005-918921
日期:——
The coupling reaction of aryl iodides with acetylacetone or ethyl cyanoacetate under catalysis of CuI/l-proline works at relatively mild conditions to provide 3-aryl-2, 4-pentanediones and α-aryl cyanoacetates in moderate to good yields.
Sterically encumbered biaryls are prepared in two steps by Cul-proline-catalyzed arylation of acetylacetone to give 3-arylpentane-2,4-diones and subsequent formal [3+3] cyclization of the latter with 1,3-bis(trimethylsilyloxy)-1,3-dienes. (C) 2008 Elsevier Ltd. All rights reserved.
Synthesis of of sterically encumbered biaryls based on a ‘copper(I)-catalyzed arylation/[3+3] cyclocondensation’ strategy
Sterically encumbered biaryls are prepared in two steps by combination of the CuI-proline-catalyzed arylation of acetylacetone with formal [3+3] cyclizations of 1,3-bis(trimethylsilyloxy)-1,3-dienes. In addition, the synthesis of 4,6- and 5,6-diarylsalicylates based on [3+3] cyclizations is reported. (C) 2010 Elsevier Ltd. All rights reserved.
Beta-Diketone Ancillary Ligands and Their Metal Complexes Used in Organic Optoelectronic Devices
申请人:Cheng Chien-Hong
公开号:US20100270915A1
公开(公告)日:2010-10-28
The present invention discloses a phosphor material for organic optoelectronic devices. The phosphor is a complex comprising a metal (Ir or Pt) and an aryl-modified beta-diketone ligand. The complexes of this invention are useful to function as an emitter in the emissive layer of an organic light emitting diode, even as the complex is the main component of this layer.