tert-butyl 1-benzyl-1,6-diazaspiro[3.3]heptane-6-carboxylate(WXC05331) synthesis

Yield:1431868-59-5 1.79 g

Reaction Conditions:

Stage #1: 1-benzyl-1,6-diaza-spiro[3.3]heptane oxalatewith triethylamine in methanol; for 0.0833333 h;
Stage #2: di-tert-butyl dicarbonate in methanol at 20;

Steps:

5.a a) tert-Butyl 1-benzyl-1,6-diazaspiro[3.3]heptane-6-carboxylate

To a solution of 1-benzyl-1,6-diaza-spiro[3.3]heptane oxalate (1.55 g, 3.32 mmol) in methanol (10 mL) was added triethylamine (1.85 mL, 13.3 mmol). After 5 min, Boc₂O (1.7 mL, 7.31 mmol) was added and the reaction mixture was stirred at ambient temperature overnight, and was then concentrated under reduced pressure. Trituration with diethyl ether and concentration of the resulting filtrate afforded the title compound (1.79 g) as a yellow oil. MS (EI) m/e: 289.1 (M+H)⁺.

References:

US2013/109668,2013,A1 Location in patent:Paragraph 0226-0227