Silver(I)-Catalyzed Diastereoselective Hydroborylation of Cyclopropenes
Ming Huang1, Changsheng Zhou1, Ke-Fang Yang1
1Hangzhou Normal University, College of Material Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Key Laboratory of Organosilicon Material Technology of Zhejiang Province, Hangzhou 311121, China.
None:
An effective (NHC)AgCl catalysis was developed in the hydroborylation of cyclopropenes with B2pin2, delivering a variety of cyclopylboronates in a stereoselective manner, which could be easily transformed for the construction of versatile cyclopropanes. This protocol works effectively under mild reaction conditions in an open-air atmosphere, and it was easy to apply on a gram scale. This novel method in detail was also explored by control experiments, providing a number of key insights. The kinetic process followed by 1H NMR indicated that the reaction was finished in 15 min. Furthermore, the mechanism of silver(I)-catalyzed hydroborylation of cyclopropenes was proposed, with the protonation by methanol as the rate-determining step.
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