1380313-74-5Relevant academic research and scientific papers
Cobalt(I)-Catalyzed Borylation of Unactivated Alkyl Bromides and Chlorides
Geetharani, K.,Prasad, K. Sujit,Varghese, Dominic,Verma, Piyush Kumar
, p. 1431 - 1436 (2020)
A cobalt-complex-catalyzed borylation of a wide range of alkyl halides with a diboron reagent (B2pin2 or B2neop2) has been developed under mild reaction conditions, demonstrating the first cobalt-mediated cross-coupling with alkyl electrophiles. This protocol allows alkyl boronic esters to be accessed from alkyl halides, including alkyl chlorides, which were used rarely as coupling partners. Mechanistic studies reveal the possible involvement of an alkyl radical intermediate in this cobalt-mediated catalytic cycle.
Metal catalyst-free photo-induced alkyl C-O bond borylation
Chen, Changzhou,Gong, Hegui,Lei, Chuanhu,Ma, Guobin,Talukdar, Sangita,Zhao, Xinluo
, p. 10219 - 10222 (2020/09/18)
Metal catalyst free, blue visible light-induced C-O bond borylation of unactivated tertiary alkyl methyl oxalates has been developed to furnish tertiary alkyl boronates. From the secondary alcohols activated with imidazolylthionyl, moderate yields of boronates were attained under standard photo-induced conditions. Preliminary mechanistic studies confirmed the involvement of a (DMF)2-B2cat2 adduct that weakly absorbs light at 437 nm so as to initiate a Bcat radical. A radical-chain process is proposed wherein the alkyl radical is engaged. This journal is
α-C-H borylation of secondary alcohols: Via Ru/Fe relay catalysis: Building a platform for alcoholic C-H/C-O functionalizations
Zhu, Qing,He, Zeyu,Wang, Lu,Hu, Yue,Xia, Chungu,Liu, Chao
, p. 11884 - 11887 (2019/10/11)
An unprecedented α-C-H borylation of secondary alcohols was successfully achieved and delivered various tertiary α-boryl alcohols via [Ru]/[Fe] relay catalysis. The dehydrogenation catalyst (Ru) and borylation catalyst (Fe) interacted to increase the chemoselectivity. By installing the "platform functional group" Bpin via this α-C-H borylation, several alcoholic α-C-H and C-O bond functionalizations were successfully achieved.
Deoxygenative Borylation of Secondary and Tertiary Alcohols
Friese, Florian W.,Studer, Armido
supporting information, p. 9561 - 9564 (2019/06/21)
Two different approaches for the deoxygenative radical borylation of secondary and tertiary alcohols are presented. These transformations either proceed through a metal-free silyl-radical-mediated pathway or utilize visible-light photoredox catalysis. Readily available xanthates or methyl oxalates are used as radical precursors. The reactions show broad substrate scope and high functional-group tolerance, and are conducted under mild and practical conditions.
Synthesis of Secondary and Tertiary Alkyl Boronic Esters by gem-Carboborylation: Carbonyl Compounds as Bis(electrophile) Equivalents
Shi, Dunfa,Wang, Lu,Xia, Chungu,Liu, Chao
supporting information, p. 10318 - 10322 (2018/07/31)
An unprecedent gem-carboborylation of aldehydes and ketones provides access to various secondary and tertiary alkyl boronic esters. The addition of B2pin2 to a carbonyl compound generates α-oxyl-substituted alkyl boron species. Organ
Nickel-catalyzed coupling reactions of alkyl electrophiles, including unactivated tertiary halides, to generate carbon-boron bonds
Dudnik, Alexander S.,Fu, Gregory C.
, p. 10693 - 10697 (2012/08/08)
Through the use of a catalyst formed in situ from NiBr2? diglyme and a pybox ligand (both of which are commercially available), we have achieved our first examples of coupling reactions of unactivated tertiary alkyl electrophiles, as well as our first success with nickel-catalyzed couplings that generate bonds other than C-C bonds. Specifically, we have determined that this catalyst accomplishes Miyaura-type borylations of unactivated tertiary, secondary, and primary alkyl halides with diboron reagents to furnish alkylboronates, a family of compounds with substantial (and expanding) utility, under mild conditions; indeed, the umpolung borylation of a tertiary alkyl bromide can be achieved at a temperature as low as -10 °C. The method exhibits good functional-group compatibility and is regiospecific, both of which can be issues with traditional approaches to the synthesis of alkylboronates. In contrast to seemingly related nickel-catalyzed C-C bond-forming processes, tertiary halides are more reactive than secondary or primary halides in this nickel-catalyzed C-B bond-forming reaction; this divergence is particularly noteworthy in view of the likelihood that both transformations follow an inner-sphere electron-transfer pathway for oxidative addition.
