Quelques aspects de la reactivite de l'α-chloro α-ethoxymethyltributyletain : etherification reductrice des aldehydes aromatiques et mise en evidence de formyltributyletain lors de la reaction d'hydrolyse
Acylstannanes were found to add to such alpha,beta-unsaturated carbonylcompounds as enones or ynoates in the presence of a nicel or palladium catalyst to give 2-stannyl-4-oxoalk-2-enoates or 1,4-diketones, whereas the three component coupling between acylstannanes, enones and aldehydes provided 2-hydroxymethyl 1,4-diketones.
Carbostannylation of 1,2-dienes using acyl- and alkynylstannanes was achieved by means of nickel catalysis. In particular, acylstannylation of 1,2-dienes could be carried out with bis(1,5-cyclooctadiene)nickel [Ni(cod)2] and acylstannanes to give selectively α-acylmethyl(vinyl)stannanes. The reaction was also applicable to acylstannanes prepared in situ by protonolysis of α-alkoxyalkenylstannanes or
Unsymmetrical α -diketones have been obtained via cross coupling of acyltins with acylhalides under PdCl2(PPh3)2 catalysis while symmetrical α -diketones have been readily obtained via “in situ” formation of acyltins using hexabutylditin and acyl chlorides under similar experimental conditions.
A new approach to carbon–carbon bond formation: development of aerobic Pd-catalyzed reductive coupling reactions of organometallic reagents and styrenes
作者:Keith M. Gligorich、Yasumasa Iwai、Sarah A. Cummings、Matthew S. Sigman
DOI:10.1016/j.tet.2009.03.096
日期:2009.6
Alkenes are attractive starting materials for organic synthesis and the development of new selective functionalization reactions is desired. Previously, our laboratory discovered a unique Pd-catalyzed hydroalkoxylation reaction of styrenes containing a phenol. Based upon deuterium labeling experiments, a mechanism involving an aerobicalcoholoxidationcoupled to alkene functionalization was proposed
Nickel-catalysed acylstannylation of 1,2-dienes: synthesis and reactions of α-(acylmethyl)vinylstannanes
作者:Eiji Shirakawa、Yoshiaki Nakao、Tamejiro Hiyama
DOI:10.1039/b008190f
日期:——
Bis(cycloocta-1,5-diene)nickel was found to be an effective
catalyst for the acylstannylation of 1,2-dienes to give a wide variety of
α-(acylmethyl)vinylstannanes, which were transformed to variously
substituted conjugated and unconjugated enones by carbonâcarbon bond
forming reactions.