Tetrahydrofuran → Ethyl 2-(diphenylmethyleneamino)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)hexanoate

Participants

Reaction Conditions

Reaction Steps

A solution of N-(diphenylmethylene)glycine ethyl ester (8.24 g, 30.8 mmol) and 2-(4-bromobutyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (8.92 g, 33.9 mmol) in freshly distilled THF (77 mL, 0.4 M) was cooled to −78° C. and treated with lithium bis(trimethylsilyl)amide (32.3 mL, 1.0 M in THF). Once the addition was complete, the reaction was warmed to 50° C. and heated for 8 h. After being complete by TLC, the reaction mixture was cooled to 0° C., diluted with ethyl acetate and washed successively with saturated aqueous NaHCO3 and saturated aqueous NaCl, dried over MgSO4, filtered and concentrated. Rapid purification by MPLC (1-15% ethyl acetate in heptane with 0.5% triethylamine over 6 CV) gave ethyl 2-(diphenylmethyleneamino)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)hexanoate as a colorless oil (8.9 g, 64%). Rf 0.40 (30% ethyl acetate in heptane).

Provenance & Evidence