Hexane → 1-(4-(((tert-Butyl(dimethyl)silyl)oxy)methyl)phenyl)-2,2,2-trifluoroethan-1-one

Beteiligte Stoffe

Reaktionsschritte

To a stirred solution of the (4-bromobenzyloxy)-(tert.-butyl)-dimethylsilane (24.94 g, 82.8 mmol) in THF (420 mL) at −78° C. was added dropwise a 1.6 M solution of nBuLi in hexane (62 mL, 99.2 mmol) over a 1 h period. After stirring the mixture at the same temperature for 75 min, a solution of N,N-diethyltrifluoroacetamide (19.19 g, 113 nmol) in THF (60 mL) was added dropwise over 1 h. Following the addition the mixture at −78° C. for a further 75 min before the reaction was quenched with an aqueous solution of NH4Cl. Ether was added and the organic layer was extracted 3 times with ether (3×300 mL). The organic layers were combined, dried over Na2SO4 and concentrated in vacuum. The resulting pale yellow liquid was distillated in vacuo to give the 1-(4-((tert-butyldimethylsilyloxy)methyl)phenyl)-2,2,2-trifluoroethanone (65%) as a colorless liquid; b.p. 170-180° C. (10 torr), 1H NMR (CDCl3): δ 0.12 (s, (CH3)2Si), 0.96 (s, CH3)3C), 4.83 (s, CH2), 7.50 (d, J=8.2 Hz, C6H4), 8.05 (d, J=8.2 Hz, C6H4); 13C NMR (CDCl3): δ −5.4 (CH3Si), 18.3 (C(CH3)3), 25.8 (C(CH3)3), 64.2 (CH2O), 116.7 (q, J=289.7 Hz, CF3), 126.2 (C6H2), 128.6 (C6H2), 130.2 (C6H2), 150.1, (C6H2), 180.2 (q, J=34.5 Hz, CO).

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