Steric and Electronic Effects Influencing β-Aryl Elimination in the Pd-catalyzed Carbon–Carbon Single Bond Activation of Triarylmethanols

• DOI: 10.1021/jo302592g
• Publication Date: 2013-01-24T14:14:16Z
• Authors: James R. Bour; Jacob C. Green; Valerie J. Winton; Jeffrey B. Johnson
• Keywords: CLEAVAGE; IMINYL COMPLEXES; C-C-BOND; NICKEL; RHODIUM; 01 natural sciences; REACTIVITY; 0104 chemical sciences; ALPHA; Chemistry; H BOND; OXIDATIVE ADDITION; ALPHA-DISUBSTITUTED ARYLMETHANOLS; Physical Sciences and Mathematics; BENZONITRILE

An analysis of the palladium-catalyzed activation of carbon-carbon single bonds within triarylmethanols has led to a greater understanding of factors influencing the β-aryl elimination process responsible for C-C bond cleavage. A series of competition reactions were utilized to determine that β-aryl elimination of aryl substituents containing ortho-substitution proceeds with significant preference to unsubstituted phenyl rings. Further experiments indicate that substrates containing either strongly donating or withdrawing substituents are cleaved from triarylmethanols more readily than relatively neutral species.