Theoretical elucidation of the potential possibility of synthesizing arylboronic acids via Rh-catalytic borylations of aryl acetylene and aryl ethylene

• Published in: Journal of organometallic chemistry Vol. 831; pp. 36 - 44
• Main Authors: Han, Zhe, Yan, Jing, Zhu, Ying, Yi, Guanyu, Liu, Chengbu, Zhang, Dongju
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2017
• Subjects: Borylation reactions; DFT; Organoboron compounds; Rh(I) catalysis; Borylation reactions; Rh(I) catalysis; DFT; Organoboron compounds
• ISSN: 0022-328X; 1872-8561
• DOI: 10.1016/j.jorganchem.2017.01.001

As a new type of catalytic borylations, the Rh-catalytic borylation reaction of aryl cyanides has been reported experimentally (Tobisu et al. J. Am. Soc. Chem. 2012, 134, 115). Here, to aid experimental designs of the novel type of borylation reactions, we theoretically predict Rh-catalytic borylations of two alternative substrates of aryl cyanides, i.e. aryl acetylene and aryl ethylene. Both borylation and diborylation pathways have been calculated in details for each substrate. It is found that aryl ethylene prefers to the borylation product via the β-H elimination mechanism, in contrast, aryl acetylene favors the diborylation product by inserting the CC bond into the RhB bond. The theoretical results are expected to be helpful for the preparation of organoboron compounds. DFT calculation results showed diborylation of aryl acetylene and borylation of aryl ethylene are thermodynamically and kinetically favorable. [Display omitted] •Catalytic borylations of aryl acetylene and aryl ethylene are designed and calculated theoretically.•Aryl acetylene favors the diborylation product by inserting the CC bond into the RhB bond.•Aryl ethylene prefers the borylation product by breaking its terminal hydrogen-vinyl bond.•The borylation of aryl ethylene is more favorable than ones of aryl acetylene and aryl cyanide.