Hydrochloric Acid → 1,2,3,4,7,8,9,10-Octahydrophenanthridine-4-carbothioamide

Participants

Reaction Steps

A solution of 1,2,3,4,7,8,9,10-Octahydrophenanthridine (17.1 g, 0.91 mole) in benzene (100 ml.) was cooled to 0° C. and treated portionwise under an inert atmosphere with a 9% w/v solution of n-butyl-lithium in hexane (40 ml. 0.56 mole). After the addition was complete the mixture was stirred for a further 0.5 h and the resulting 4-lithio-1,2,3,4,7,8,9,10-octahydrophenanthridine then treated in situ with trimethylsilylisothiocyanate (13 ml., 0.91 mole) and stirred a further hour. The reaction mixture was treated with 2N HCl (100 ml.), the layers separated and the aqueous layer washed with ethyl acetate (100 ml.). The pH of the aqueous solution was adjusted to 9 with Na2CO3 and the solution was extracted with chloroform (3 × 100 ml.). Drying (MgSO4) and evaporation of the combined organic layers gave a yellow oil which crystallised in trituration with hexane. Recrystallisation of the solid from benzene gave the title compound as white needles (4 g, 18%) M.P. 162° C.

Provenance & Evidence