Triphenylphosphine → 2E-5-trimethylsilylpent-2-en-4-ynyltriphenylphosphonium bromide

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Reaction Steps

Triphenylphosphine (64.1 g, 0.244 mol) was added to a solution of 1-bromo-5-trimethylsilylpent-2-en-4-yne (44.26 g, 0.204 mol) in toluene (204 mL). The mixture was stirred at ambient temperature under a nitrogen atmosphere. After 3 days the suspension was diluted with methyl tert-butyl ether (408 mL), stirred for 1 hour at ambient temperature, and the precipitate was collected by filtration. The filter cake was washed with methyl tert-butyl ether and dried under vacuum at 30° C. to get 79 g of 2E-5-trimethylsilylpent-2-en-4-ynyltriphenyl-phosphonium bromide, a compound of formula (Q), as an off-white powder: 1H-NMR (300 mHz, CDCl3) δ 0.14 (s, 9H), 5.08 (dd, 2H), 5.91 (dt, 1H), 6.22 (dd, 1H), 7.6–8.0 (m, 15 H); Anal. Calculated for C26H28BrPSi requires C, 65.13; H, 5.89; Br, 16.66; P, 6.46. found C, 64.95; H, 5.78; Br, 16.96; P, 6.31.

Provenance & Evidence