2-[3,4-Bis(tert-butyldimethylsilanyloxy-methyl)phenoxymethyl]-5-((e)-4,4-dibromo-1-ethylbuta-1,3-dienyl)thiophene → 2-[3,4-bis(tert-butyldimethylsilanyloxymethyl)phenoxymethyl]-5-((E)-1-ethyl-but-1-en-3-ynyl)thiophene

Participants

Reaction Conditions

Reaction Steps

3.9 g (5.4 mmol) of 2-[3,4-bis(tert-butyldimethylsilanyloxymethyl)phenoxymethyl]-5-((E)-4,4-dibromo-1-ethylbuta-1,3-dienyl)thiophene are dissolved in 100 mL of THF and the mixture is cooled to −78° C. 4.4 mL (11 mmol) of 2.5 M butyllithium are added slowly and the reaction medium is stirred at the same temperature for 1 hour. After the usual treatment and chromatography on silica gel (eluent: 96 heptane/4 ethyl acetate), the desired product is obtained in the form of a brown oil.

Provenance & Evidence