ortho,ortho′-Substituted KITPHOS Monophosphines: Highly Efficient Ligands for Palladium-Catalyzed CC and CN Bond Formation

✍ Scribed by Simon Doherty; Julian G. Knight; John P. McGrady; Alexandra M. Ferguson; Nicholas A. B. Ward; Ross W. Harrington; William Clegg

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 295 KB
• Volume: 352
• Category: Article
• ISSN: 1615-4150
• DOI: 10.1002/adsc.200900577

✦ Synopsis

Abstract

__ortho,ortho′‐__Substitution of the phosphinoalkyne‐derived aryl ring in KITPHOS (11‐dicyclohexylphosphino‐12‐phenyl‐9,10‐ethenoanthracene) monophosphines enhances the performance of this class of ligand in palladium‐catalyzed Suzuki–Miyaura cross‐couplings and Buchwald–Hartwig aminations, compared with their unsubstituted and mono‐substituted counterparts. An alternative complementary synthesis of KITPHOS monophosphines has been developed and two new members of this family, 2,6‐Me~2~‐KITPHOS [11‐dicyclohexylphosphino‐12‐(2,6‐dimethylphenyl)‐9,10‐ethenoanthracene] and 2,6‐(MeO)~2~‐KITPHOS [11‐dicyclohexylphosphino‐12‐(2,6‐dimethoxyphenyl)‐9,10‐ethenoanthracene], have been prepared; palladium complexes of both are highly efficient catalysts for CC and CN bond formation with a range of electron‐rich and electron‐poor aromatic chlorides as well as heteroaryl chlorides.