Piperidine → Ethyl 2-(4-oxo-4H-naphtho[1,2-b]pyran-2-yl)cyclopropane carboxylate

Participants

Reaction Steps

A mixture of 12.4g of 1'-hydroxy-2-(methylsulfinyl)-2'-acetonaphthone, 7.1g of ethyl 2-formyl-1-cyclopropane carboxylate, 250ml of toluene and 0.5ml of piperidine was refluxed for 8 hrs. The toluene was then removed under reduced pressure, and the oily residue was recrystallized from Skelly B with the aid of charcoal, mp. 106°-07.5°; yield 6.5g (42%); λ max mμ (ε) 219 (50,000), 259 (36,800), 327 (3,990), 341 (4,100); ν max 760 (m), 825 (ms), 1195 (s), 1640 (s), 1650 (s), 1730 (s) cm-1.

Provenance & Evidence