Propargyl alcohols Butyllithium

Propargylic alcohols. Butyllithium serves as a base and a nucleophile in the three-component reaction, also involving a terminal acetylene and an 7Y,A(-disubsti-tuted amide. 

Butyllithium in a mixture of hexane and diethyl ether or THE can presumably also be used for the dilithiation of propargyl alcohol. 

The synthesis of enantiomerically pure propargylic alcohols is possible using the same methodology 43b. Thus, addition of (—)-[(l-chloro-2-phenylethyl)sulfinyl]-4-methylbenzene (14) to propan-al led to a mixture of the diastereomers 15A/15B (d.r. 44 56) which are easily separated by column chromatography. After thermal elimination of the sulfinyl group the vinyl chlorides 16A/16B were obtained as a mixture of E- and Z-oleftns. Elimination of hydrogen chloride was carried out with three equivalents of butyllithium, leading to enantiomerically pure 1 -phenyl-1-pentyn-3-ol. 

Better intermolecular yields were obtained by switching over to propargylic alcohol a reaction which is already known to work with Grignard reagents The yield was 48 % using ethyllithium, but n-butyllithium and phenyllithium have also been added in 15% and 42% yield, respectively The reaction is catalyzed by 10% copper(I) iodide. Without this catalyst the yields are only about half of the... 

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... 

Amino aldehydes can also be condensed with tiiphenylphosphonium ylids in a Wittig olefination reaction.134 Generation of the propargyl alcohol derivative 1.228 allowed conversion of the hydroxyl group to a bromide and then to the triphenyl-phosphonium salt. Treatment with n-butyllithium gave the ylid, which reacted with... 

Like Grignard reagents, " organolithiums can add onto the triple bond of propargylic alcohols. Thus, -butyllithium combines with 3-phenyl-2-propyn-l-ol to give, after hydrolysis, 2-butyl-3-phenyl-2-propen-l-ol almost quantitatively. ... 

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