4381-02-6Relevant articles and documents
Salt-Stabilized Silylzinc Pivalates for Nickel-Catalyzed Carbosilylation of Alkenes
Chen, Kaixin,Dong, Shoucheng,Duan, Zhili,Li, Jie,Liu, Xingchen,Wang, Jixin
supporting information, (2022/03/03)
We herein report the preparation of solid and salt-stabilized silylzinc pivalates from the corresponding silyllithium reagents via transmetalation with Zn(OPiv)2. These resulting organosilylzinc pivalates show enhanced air and moisture stability and unique reactivity in the silylative difunctionalization of alkenes. Thus, a practical chelation-assisted nickel-catalyzed regioselective alkyl and benzylsilylation of alkenes has been developed, which provides an easy method to access alkyl silanes with broad substrate scope and wide functional group compatibility. Kinetic experiments highlight that the OPiv-coordination is crucial to improve the reactivity of silylzinc pivalates. Furthermore, late-stage functionalizations of druglike molecules and versatile modifications of the products illustrate the synthetical utility of this protocol.
Synthesis of dimeric molecules via ag-catalyzed electrochemical homocoupling of organic bromides paired with electrooxidation of urea
Klinkova, Anna,Krivoshapkina, Elena F.,Medvedev, Jury J.,Medvedeva, Xenia V.,Pivovarova, Yekaterina,Steksova, Yulia P.
, (2020/11/09)
We present a sacrificial anode-free approach to reductive homocoupling of organohalides that does not require a co-catalyst. In this approach, a divided electrochemical cell with aprotic and aqueous compartments separated by an anion exchange membrane enables coupling of the cathodic homocoupling reaction with anodic oxidation of urea. We show that, in contrast with traditional one-compartment cells relying on sacrificial anodes, the proposed cell configuration maintains stable cell voltage in the course of galvanostatic electrolysis. A synthetic potential of this method was assessed using a series of 13 organic bromides that demonstrated a strong dependence of the reaction outcome on the structure of the organic substrate, more specifically, the dissociation energy of the C–Br bond and the redox properties of formed radicals, which are discussed in detail. While not being suitable for the synthesis of byarylstructures, this method is excellent for C(sp3)-C(sp3) coupling to corresponding dimeric products with up to quantitative yields. Simultaneous electrochemical treatment of nitrogenous waste in the adjacent half-cell provides an additional incentive for wide adaptation of this sustainable synthetic approach.
Luminescent tungsten(vi) complexes as photocatalysts for light-driven C-C and C-B bond formation reactions
Chan, Kaai-Tung,Che, Chi-Ming,Du, Lili,Liu, Yungen,Phillips, David Lee,To, Wai-Pong,Tong, Glenna So Ming,Wu, Liang-Liang,Yu, Daohong
, p. 6370 - 6382 (2020/07/15)
The realization of photocatalysis for practical synthetic application hinges on the development of inexpensive photocatalysts which can be prepared on a large scale. Herein an air-stable, visible-light-absorbing photoluminescent tungsten(vi) complex which can be conveniently prepared at the gram-scale is described. This complex could catalyse photochemical organic transformation reactions including borylation of aryl halides, such as aryl chloride, reductive coupling of benzyl bromides for C-C bond formation, reductive coupling of phenacyl bromides, and decarboxylative coupling of redox-active esters of alkyl carboxylic acid with high product yields and broad functional group tolerance.
