Propargylic mesylate carbonylation

Besides alkoxy-, amino-, and amidocarbonylation reactions, a carbonylation process using a thiol as nucleophile, that is, thiocarbonylation, has been extensively studied.It has been shown that the thiocarbonylation takes place with 1-alkynes, " " " propargyl alcohols,allenes, " 1,3-dienes, propargylic mesylates, " and bicyclopropylidene . 

AUylation and propargylation reactions. In the presence of the (Ph3P)4Pd catalyst, indium(I) iodide form organoindium(III) reagents with allylic halides and propargylic mesylates that react with carbonyl compounds in various solvents. 

The allenic acid 63, obtained by the carbonylation of the chiral propargyl mesylate 62, was converted stereospecihcally to the butenolide 64 by treatment with AgNOj as a catalyst. Racemization occurred by the carbonylation of the... 

Masuyama, Y. Watabe, A. Kurusu, Y. Carbonyl allenylations and propargylations by 3-chloro-l-propyne or 2-propynyl mesylates with SnCl4 and Bu4NI. Synlett 2003,1713— 1715. 

Scheme 11.16 Carbonylation of propargylic acetate, bromide, and mesylate.

As noted above, alkyne anions are very useful in Sn2 reactions with alkyl halides, and in acyl addition reactions to a carbonyl.46 Alkyl halides and sulfonate esters (tosylates and mesylates primarily) serve as electrophilic substrates for acetylides. A simple example is taken from Kaiser s synthesis of niphatoxin B, in which propargyl alcohol (36) is treated with butyllithium and then the OTHP derivative of 8-bromo-1-octanol to give a 47% yield of 37.48... 

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