Synthesis of adamantyl substituted 1,2,3-triazol-5-ylidene ligands and their PEPPSI-type palladium complexes
摘要:
PEPPSI-type Pd-complexes with the bulky mesoionic 1,2,3-triazolium carbenes (tzNHC) substituted by the adamantyl groups were prepared from 1-azidoadamantane and 1-ethynyladamantane. The X-ray analysis revealed that 1,4-diadamantyl-tzNHC complex (TAd-PEPPSI) showed longer Pd-C bond length than 1-adamantyl-4-phenyl-tzNHC complex (TAdPh-PEPPSI) and 1,4-diphenyl-tzNHC complex (TPh-PEPPSI). These complexes were applied to Hiyama coupling reaction between aryl bromides and phenyltrimethoxysilane. TAd-PEPPSI rapidly initiates the reaction, and TAdPh-PEPPSI gave good product yields. (C) 2015 Elsevier Ltd. All rights reserved.
Synthesis of adamantane derivatives. 52. 1,3-Dipolar cycloaddition reactions of 1-azidoadamantane. Reactivity, regioselectivity, and carbon-13 nuclear magnetic resonance spectra of 1-(1-adamantyl)-.DELTA.2-1,2,3-triazolines and -1H-1,2,3-triazoles