Origin of Reactivity Difference between Phosphines and Phosphinites in Ru-Catalyzed Phosphorus-Directed sp²C–H Borylation: Mechanistic Study and Improvement of Reaction Conditions

Bulletin of the Chemical Society of Japan, Journal Year: 2023, Volume and Issue: 96(9), P. 842 - 848

Published: July 24, 2023

The reaction mechanism of Ru-catalyzed phosphorus-directed ortho sp2C–H borylation triarylphosphines and aryl phosphinites was investigated. Competition experiments time course analyses clarified the existence an induction period when using [RuCl2(p-cymene)]2 as a catalyst, which attributed to substitution p-cymene ligand by phosphorus compounds generate reactive species. These studies have reasonably explained origin reactivity difference between phosphinites. Dramatic improvement conditions for achieved employing RuCl2(dmso)4 new catalyst based on mechanistic insights, realizing at room temperature. Mechanistic investigations [RuCl2(p-cymene)]2-catalyzed substrates p-cymene-free active Ru Based these results, catalyst.

Language: Английский

Atroposelective Ir-Catalyzed C–H Borylation of Phthalazine Heterobiaryls

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(19), P. 14222 - 14226

Published: Sept. 26, 2023

The atroposelective iridium-catalyzed borylation of menthyloxy-substituted phthalazine heterobiaryls with diborons is reported. Utilizing [Ir(OMe)(COD)]2/2-aminopyridine as a rarely used efficient catalyst system, the were selectively borylated in 2-position carbocycle, exclusively yielding only one atropisomers, depending on substitution (+)-menthyl or (-)-menthyl moieties. Exemplary further functionalization atropisomer demonstrated that nickel-catalyzed Suzuki-Miyaura cross-coupling an aryl halide was able to provide stereoretention certain degree (up 75% de).

Language: Английский