Regioselective Rhodium-Catalyzed Addition of 1,3-Dicarbonyl Compounds to Terminal Alkynes
作者:Thorsten M. Beck、Bernhard Breit
DOI:10.1021/acs.orglett.5b03391
日期:2016.1.4
A new method for the rhodium-catalyzed regioselective C–C bond formation using terminal alkynes and 1,3-dicarbonyl compounds to achieve valuable branched α-allylated 1,3-dicarbonyl products is reported. With a Rh(I)/DPEphos/p-CF3-benzoic acid as the catalyst system, the desired products can be obtained in good to excellent yields and with perfect regioselectivity. A broad range of functional groups
NHC–copper hydrides as chemoselective reducing agents: catalytic reduction of alkynes, alkyl triflates, and alkyl halides
作者:Nick Cox、Hester Dang、Aaron M. Whittaker、Gojko Lalic
DOI:10.1016/j.tet.2014.04.004
日期:2014.7
as well as the NHC–copper-catalyzed reduction of primary alkyl triflates and primary and secondary alkyl iodides and bromides are described. The high chemoselectivity demonstrated in these examples illustrates the mild nature of copper hydride complexes as reducing agents, which have applications in synthetic chemistry beyond their traditional role in the reduction of activated alkenes and carbonyl compounds
The Palladium-Catalyzed Anti-Markovnikov Hydroalkylation of Allylic Alcohol Derivatives
作者:Ryan J. DeLuca、Matthew S. Sigman
DOI:10.1021/ol303129p
日期:2013.1.4
A palladium-catalyzed hydroalkylation reaction of protected allylicalcohols using alkylzinc bromide reagents is reported. This account includes numerous allylic, homoallylic, and bishomoallylic alcoholderivatives, all with a uniform selectivity of >20:1 for the anti-Markovnikov product. The reaction features the ability to deliver enantiomerically enriched alcohols in unfunctionalized regions, which
Monophasic Catalytic System for the Selective Semireduction of Alkynes
作者:Aaron M Whittaker、Gojko Lalic
DOI:10.1021/ol4001679
日期:2013.3.1
A highly efficient semireduction of alkynes has been developed. Using 0.5–2 mol % of a copper catalyst, semireduction can be accomplished with a wide range of substrates, including both internal and terminal alkynes without over-reduction. The new method has excellent chemoselectivity, and the semireduction can be accomplished even in the presence of nitro and aryl iodo groups. Finally, commercial
Cu(OTf)2 - DBN/DBU complex as an efficient catalyst for allylic oxidation of olefins with tert-butyl perbenzoate
作者:Govindasamy Sekar、Arpita DattaGupta、Vinod K. Singh
DOI:10.1016/0040-4039(96)01911-9
日期:1996.11
Olefins, on treatment with tert-butyl perbenzoate in the presence of a catalytic amount of a complex of Cu(OTf)2 and chelating ligands such as DBN and DBU gave allylic benzoates under milder conditions. A variety of olefins were tested in the reaction.