Ethylene Glycol → 7-Methyl 8-(phenylmethyl) 1,4-dioxa-8-azaspiro[4.5]decane-7,8-dicarboxylate

Participants

Reaction Steps

A solution of the product of stage (ii) (5.06 g) and 1,2-ethanediol (1.06 ml) in benzene (100 ml) containing 4-toluenesulphonic acid (0.2 g) was stirred at reflux temperature under a Soxhlet cup filled with 4 Å molecular sieves for 4 h. The reaction mixture was allowed to cool to 22°, washed with 2N sodium carbonate (2×20 ml), water (20 ml) and dried. The benzene solution was evaporated in vacuo to give the title compound as an oil (5.75 g).

Provenance & Evidence