Azolium Salts as Effective Catalysts for Benzoin Condensation and Related Reactions
摘要:
A catalytic ability of several azolium salts for benzoin condensation, the benzoylation of 4-chloro-1-phenyl-1H-pyrazolo[3,4-d]pyrimidine, and oxidative aroylation was examined. We found that azolium salts having an imidazolium moiety, such as 1,4-dimethyl-1,2,4-triazolium iodide (3), and 2-methylpyrido[1,2-c]- (4), dipyrido[1,2-c:2',1'-e]- (5), naphtho[1,2-c]- (10), and phenanthro[9,10-c]imidazolium iodide (11) can be used as effective catalysts for benzoin condensation and related reactions.
Transfer Semihydrogenation of Alkynes Catalyzed by Imidazo[1,5-<i>a</i>]pyrid-3-ylidene–Pd Complexes: Positive Effects of Electronic and Steric Features on N-Heterocyclic Carbene Ligands
To investigate the catalytic utility of the imidazo[1,5-a]pyrid-3-ylidene (IPC) ligand, Pd-catalyzed transfer semihydrogenation of alkynes with formic acid as a hydrogen source was conducted. The s...
A simple Ni(II)-catalyzed C–H hydroarylation of diarylacetylenes with imidazolium salts without adding any ligand was developed. It provides a facile and efficient access to (E)-2-(1,2-diarylvinyl)imidazolium salts. The preliminary results indicate a rare nonredox catalytic cycle of Ni(II), complementary to the common redox catalytic cycle starting from Ni(0).
开发了一种简单的 Ni( II ) 催化的二芳基乙炔与咪唑盐的 C-H 加氢芳基化,无需添加任何配体。它提供了一种简便有效的获得 ( E )-2-(1,2-二芳基乙烯基)咪唑盐的途径。初步结果表明 Ni( II ) 的罕见非氧化还原催化循环与从 Ni(0) 开始的常见氧化还原催化循环互补。
X-ray crystal structures of 10π- and 14π-electron pyrido-annelated N-heterocyclic carbenes
The first X-ray crystal structures of mono- and dipyridoimidazolinylidenes are presented, and the size of the carbene NâCâN angles discussed and correlated with the 13C NMR chemical shifts.
首次展示了单吡啶和双吡啶咪唑啉亚基的 X 射线晶体结构,讨论了碳烯 NâCâN 角的大小,并将其与 13C NMR 化学位移联系起来。