134414-86-1Relevant articles and documents
Copper-Catalyzed Double C(sp3)-Si Coupling of Geminal Dibromides: Ionic-to-Radical Switch in the Reaction Mechanism
Hazrati, Hamideh,Oestreich, Martin
, p. 5367 - 5369 (2018)
A method for converting geminal dibromides into 1,1-disilylated alkanes is reported. The reaction is promoted by a copper(I) catalyst generated in situ from CuBr·SMe2 as a precatalyst and 4,4′-di-tert-butyl-2,2′-bipyridine (dtbpy) as a ligand. A Si-B reagent is used as the silicon pronucleophile. It is shown that the two C(sp3)-Si bond-forming events differ in mechanism, with the first being ionic and the second being radical.
Electrophilic Fluorination of Alkenes via Bora-Wagner–Meerwein Rearrangement. Access to β-Difluoroalkyl Boronates
Biosca, Maria,Himo, Fahmi,Szabó, Kálmán J.,Wang, Qiang
supporting information, p. 26327 - 26331 (2021/11/16)
The electrophilic fluorination of geminal alkyl substituted vinyl-Bmida derivatives proceeds via bora-Wagner–Meerwein rearrangement. According to DFT modelling studies this rearrangement occurs with a low activation barrier via a bora-cyclopropane shaped TS. The Bmida group has a larger migration aptitude than the alkyl moiety in the Wagner–Meerwein rearrangement of the presented electrophilic fluorination reactions.
Hydroalkylation of Aryl Alkenes with Organohalides Catalyzed by Molybdenum Oxido Based Lewis Pairs
Belaj, Ferdinand,Dupé, Antoine,Kloki?, Sumea,M?sch-Zanetti, Nadia C.,Milinkovi?, Angela,Neshchadin, Dmytro,Rodi?, Dado,Walg, Simon,Zwettler, Niklas
, (2020/07/06)
Three molybdenum(VI) dioxido complexes [MoO2(L)2] bearing Schiff base ligands were reacted with B(C6F5)3 to afford the corresponding adducts [MoO{OB(C6F5)3}(L)2], which were fully characterized. They exhibit Frustrated Lewis-Pairs reactivity when reacting with silanes. Especially, the [MoO{OB(C6F5)3}(L)2] complex with L=2,4-dimethyl-6-((phenylimino)methyl)phenol proved to be active as catalyst for the hydroalkylation of aryl alkenes with organohalides and for the Atom-Transfer Radical Addition (ATRA) of organohalides to aliphatic alkenes. A series of gem-dichloride and gem-dibromide compounds with potential for further derivatization were synthesized from simple alkenes and organohalides, like chloroform or bromoform, using low catalyst loading. (Figure presented.).
Halogenation through Deoxygenation of Alcohols and Aldehydes
Chen, Jia,Lin, Jin-Hong,Xiao, Ji-Chang
supporting information, p. 3061 - 3064 (2018/05/28)
An efficient reagent system, Ph3P/XCH2CH2X (X = Cl, Br, or I), was very effective for the deoxygenative halogenation (including fluorination) of alcohols (including tertiary alcohols) and aldehydes. The easily available 1,2-dihaloethanes were used as key reagents and halogen sources. The use of (EtO)3P instead of Ph3P could also realize deoxy-halogenation, allowing for a convenient purification process, as the byproduct (EtO)3Pa?O could be removed by aqueous washing. The mild reaction conditions, wide substrate scope, and wide availability of 1,2-dihaloethanes make this protocol attractive for the synthesis of halogenated compounds.
A Boron Alkylidene–Alkene Cycloaddition Reaction: Application to the Synthesis of Aphanamal
Liu, Xun,Deaton, T. Maxwell,Haeffner, Fredrik,Morken, James P.
supporting information, p. 11485 - 11489 (2017/09/11)
We describe an unusual net [2+2] cycloaddition reaction between boron alkylidenes and unactivated alkenes. This reaction provides a new method for the construction of carbocyclic ring systems bearing versatile organoboronic esters. Aside from surveying the scope of this reaction, we provide details about the mechanistic underpinnings of this process, and examine its application to the synthesis of the natural product aphanamal.
Manganese-Catalyzed Borylation of Unactivated Alkyl Chlorides
Atack, Thomas C.,Cook, Silas P.
supporting information, p. 6139 - 6142 (2016/06/09)
The use of low-cost manganese(II) bromide (MnBr2) and tetramethylethylenediamine (TMEDA) catalyzes the cross coupling of (bis)pinacolatodiboron with a wide range of alkyl halides, demonstrating the first manganese-catalyzed coupling with alkyl electrophiles. This method allows access to primary, secondary, and tertiary boronic esters from the parent chlorides, which were previously inaccessible as coupling partners. The reaction proceeds in high yield with as little as 1000 ppm catalyst loading, while 5 mol % can provide high yields in as little as 30 min. Finally, radical-clock experiments revealed that at 0 °C direct borylation outcompetes alternative radical processes, thereby providing synthetically useful, temperature-controlled reaction outcomes.
Synthesis of vinyl boronates from aldehydes by a practical boron-Wittig reaction
Coombs, John R.,Zhang, Liang,Morken, James P.
supporting information, p. 1708 - 1711 (2015/04/14)
A highly stereoselective boron-Wittig reaction between stable and readily accessible 1,1-bis(pinacolboronates) and aldehydes furnishes a variety of synthetically useful di- and trisubstituted vinyl boronate esters.
Simple access to elusive α-boryl carbanions and their alkylation: An umpolung construction for organic synthesis
Hong, Kai,Liu, Xun,Morken, James P.
supporting information, p. 10581 - 10584 (2014/08/18)
The reaction of 1,1-bis(pinacolboronate) esters with alkyl halides can be effected by metal alkoxides and provides a strategy for the construction of organoboronate compounds. The reaction is found to occur by alkoxide-induced deborylation and generation of a boron-stabilized carbanion.
A method for the selective hydrogenation of alkenyl halides to alkyl halides
King, Sandra M.,Ma, Xiaoshen,Herzon, Seth B.
, p. 6884 - 6887 (2014/06/09)
A general method for the selective hydrogenation of alkenyl halides to alkyl halides is described. Fluoro, chloro, bromo, iodo, and gem-dihaloalkenes are viable substrates for the transformation. The selectivity of the hydrogenation is consistent with reduction by a hydrogen atom transfer pathway.
