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Propargylzinc bromide

Interestingly, a second allenyl adduct, isomeric with the major product, was also formed in the latter reaction. This isomer was surmised to arise by a retro reaction of the initial allenyl adduct to form a TMS propargylzinc bromide reagent, which subsequently adds to the liberated aldehyde (equation 12). The regiochemistry of this addition is also thought to be directed by steric effects, again involving the methyl and TMS substituents. [Pg.429]

An interesting 1,4-elimination reaction occurs upon treatment of allylic acetates with catalytic [Pd(Ph3P)4] together with propargylzinc bromide to act as a base (Scheme 43). What is important in this reaction is the observed regioselectivity, which is in contrast to that of previously reported palladium-catalysed elimination reactions giving conjugated dienes. [Pg.252]


See other pages where Propargylzinc bromide is mentioned: [Pg.368]    [Pg.119]    [Pg.760]    [Pg.109]    [Pg.368]    [Pg.282]    [Pg.201]    [Pg.179]    [Pg.242]    [Pg.346]    [Pg.346]    [Pg.368]    [Pg.119]    [Pg.760]    [Pg.109]    [Pg.368]    [Pg.282]    [Pg.201]    [Pg.179]    [Pg.242]    [Pg.346]    [Pg.346]    [Pg.423]    [Pg.746]    [Pg.746]   
See also in sourсe #XX -- [ Pg.464 ]




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Propargylzincation

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