Diisopropylamine → HCID 11349373, compound

Participants

Reaction Steps

To a solution of 27.62 g of dilsopropyl amine in 28 ml of THF was added at −78° 171 ml of n-BuLi (1.6 M in hexane) the solution was warmed to 0° for 30 min and cooled to −78°. The LDA-solution was treated at −78° with a solution of 59.38 g of the crude 10-tert-butoxy-1,1,1-trofluoro-6,6-dimethyl-2-trifluoromethyl-dec-3-yn-2-ol in 20 ml of THF over 40 min and stirring was continued at −78° for 1 h. The yellow solution was treated at −78° with 47.11 g of diethylchlorophosphate over 30 min, the mixture was warmed to 22° over 2 h and stirring was continued at 22° for 2 h. The suspension was added at −78° dropwise to a solution of LDA, prepared with 52.62 g diisopropyl amine, 325 ml of n-BuLi (1.6 M in hexane) and 60 ml of THF as described above, over 20 min and stirring, was continued at −78° for 2 h. The suspension containing the anion of 8-tert-butoxy-4,4-dimethyl-oct-1-yne was treated at −78° with 60.0 g of hexafluor-oacetone over 10 mim and stirring, was continued at −78° for 30 min. The suspension was washed with 300 ml of sat. aqueous NH4Cl and sat. aqueous NaCl, the organic layer was dried over MgSO4 and evaporated to give 107.9 g of crude product. The material was crystallized from 160 ml of hexane at −20° to give 43.00 g of the pure title compound as a white solid, m.p. 66-67°. The mother liquor was purified by chromatography on silica with hexane/AcOEt 19:1 to give 21.1 g of the pure title compound. IR(nujol): 3157m (OH), 2242 m (C,C-triple bond); MS(EI): 361/20 (M—CH3).

Provenance & Evidence