Manganese-Catalyzed Borylation of Unactivated Alkyl Chlorides
作者:Thomas C. Atack、Silas P. Cook
DOI:10.1021/jacs.6b03157
日期:2016.5.18
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
the reagents: the replacement of methyl by isopropyl groups led to a significant increase of reactivity. We then described a unified procedure for all deoxyhalogenations using the readily available α-chloroenamines as reagents with (bromination, iodination) or without (chlorination) an alkaline bromide or iodide. Finally, we showed that deoxyhalogenation reactions of secondary alcohols were highly
Sulfonyl halide synthesis by thiol oxyhalogenation using NBS/NCS – i PrOH
作者:Carolina Silva-Cuevas、Carlos Perez-Arrieta、Luis A. Polindara-García、J. Armando Lujan-Montelongo
DOI:10.1016/j.tetlet.2017.04.087
日期:2017.6
A rapid and facile method provides a general route to sulfonyl bromides/chlorides by the oxidation of thiols using NXS – ROH (X = Br,Cl, R = iPr) as an oxyhalogenation reagent. Control experiments suggest that the alcohol component is the source of oxygen. The proposed method enable the access to structurally diverse sulfonyl bromides and chlorides including challenging examples, inaccessible by other
一种快速而简便的方法,是使用NXS – ROH(X = Br,Cl,R = i Pr)作为氧卤代试剂氧化硫醇,从而提供了磺酰溴/氯化物的一般途径 。对照实验表明,酒精成分是氧气的来源。所提出的方法使得能够获得结构上不同的磺酰溴和氯化物,包括具有挑战性的实例,这是其他合成方法所无法达到的。
Iodobenzene Dichloride in the Esterification and Amidation of Carboxylic Acids: In-Situ Synthesis of Ph<sub>3</sub>PCl<sub>2</sub>
作者:Myriam S. Carle、Grace K. Shimokura、Graham K. Murphy
DOI:10.1002/ejoc.201600714
日期:2016.8
A novel, in-situ synthesis of dichlorotriphenylphosphorane (Ph3PCl2) is accomplished upon combining PPh3 and the easily prepared hypervalent iodine reagent iodobenzene dichloride (PhICl2). The phosphorane is selectively generated in the presence of carboxylic acid or alcohol residues to rapidly produce acyl chlorides and alkyl chlorides in high yields. Addition of EtOH, PhOH, BnOH, Et2NH or CH2N2 results
The reaction of sodium diselenide with opticallyactive alkyl tosylates or chlorides is found to be a useful method for the synthesis of opticallyactive dialkyl diselenides. Opticallyactive monoterpene diselenides derived from menthane, carane, pinane, and bornane systems have been obtained. The influence of the terpene fragment of the obtained diselenides on the diastereomeric excess of the methoxyselenylation