Regioselective Hydrogenation of Unsaturated Compounds Using Platinum-Zeolite Coupled with Organosilicon Alkoxide by CVD Method
The regioselective hydrogenation of unsaturated compounds was carried out by catalysis with platinum-zeolite coupled with an organosilicon alkoxide using a chemical vapor deposition method (CVD-modified catalyst).In hydrogenation of a mixture of 1-nonene and trans-4-nonene by this catalyst, the reaction rate of 1-nonene was much greater than that of trans-4-nonene.In particular, when diphenyldiethoxysilane was used as the coupling reagent on the platinum-zeolite, excellent selectivity was produced.Further, it was elucidated that the terminal carbon-carbon double bonds are preferentially hydrogenated in the case of some compounds possessing more than one carbon-carbon double bond.
Iron-catalysed allylation-hydrogenation sequences as masked alkyl-alkyl cross-couplings
An iron-catalysed allylation of organomagnesium reagents (alkyl, aryl) with simple allyl acetates proceeds under mild conditions (Fe(OAc)2 or Fe(acac)2, Et2O, r.t.) to furnish various alkene and styrene derivatives. Mechanistic studies indicate the operation of a homotopic catalyst. The sequential combination of such iron-catalysed allylation with an iron-catalysed hydrogenation results in overall C(sp3)-C(sp3)-bond formation that constitutes an attractive alternative to challenging direct cross-coupling protocols with alkyl halides.
Bernauer, Josef,Wu, Guojiao,Von Wangelin, Axel
p. 31217 - 31223
(2019/10/19)
Ligand effects on Negishi couplings of alkenyl halides
Negishi couplings at olefinic centers do not always occur with the anticipated maintenance of stereochemistry. The source of erosion has been traced to the ligand, and a modified method has been developed that solves the stereochemical issue and significantly improves yields of Negishi couplings in general.
Krasovskiy, Arkady,Lipshutz, Bruce H.
supporting information; experimental part
p. 3818 - 3821
(2011/10/01)
Cross-Couplings of Alkyl Electrophiles under Ligandless Conditions: Negishi Reactions of Organozirconium Reagents
This report establishes that simple, ligandless palladium complexes can catalyze the first zirconium-Negishi reactions of alkyl electrophiles. In view of the attractiveness of ligandless catalysts (cost, simplicity, and ease of purification), these observations add a significant and intriguing new dimension to the development of effective palladium-based processes for coupling alkyl electrophiles. Copyright
Wiskur, Sheryl L.,Korte, Alexander,Fu, Gregory C.
p. 82 - 83
(2007/10/03)
Alkylzirconation of alkynes catalyzed by triphenylcarbenium tetrakis(pentafluorophenyl)borate
[(C6H5)3C]+[B(C6F5)4]- effectively catalyzes the alkylmetallation of alkynes by using the alkylzirconium species, which is generated by the hydrozirconation of alkenes