Methyl chloroformate → HCID 23359463, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 50 ml of THF and 6.7 ml of diisopropylamine was cooled under N2 to -78° C. and then 17.5 ml of 2.5 M n-butyllithium in hexane was added. After 5 min. a solution of 7.8 g of the title compound of Example 4 in 15 ml of THF was added dropwise and the dark red solution that formed was stirred at -78° C. for an additional 15 min. After this time a solution of 4.6 ml of methyl chloroformate in 10 ml of THF was added dropwise and the red color dissipated rapidly. The reaction was warmed to room temperature and after 1 hr quenched with 5% aqueous sodium bicarbonate. The reaction mixture was partitioned between ether and 5% aqueous sodium bicarbonate. The ether extracts were dried over magnesium sulfate and concentrated to 14.1 g of a yellow oily solid. The crude product was triturated with ether and the resulting white precipitate was filtered and dried to afford 5.56 g of the title compound as a white solid, m.p. 234° C. to 236° C. 1H NMR(CDCl3) δ 2.1 (m, 1H), 2.75 (m, 1H) 2.95 (m, 2H), 3.71 (s, 3H), 3.75 (d, 1H, J=6Hz), 4.59 (d, 1H, J=6Hz), 7.25 (m, 2H), 7.57 (d, 2H), 7.66 (d, 2H), 7.94 (d, 1H), 8.18 (d, 1H),

Provenance & Evidence