Isopropylamine → TRANS-4-ISOPROPYLAMINO-3,4-DIHYDRO-2H-NAPHTHO[1,2-b]PYRAN-3-OL

Participants

Reaction Steps

2H-Naphtho[1,2-b]pyran (4.00 g., prepared via cyclisation of 1-naphthyl propargyl ether in diethylaniline at 210°) was converted, via the same route as that described in Example 3, to 3,4-epoxy-3,4-dihydro-2H-naphtho[1,2-b]pyran (1.44 g.) m.p. 96°-99°. This epoxide (1.40g.) was treated with isopropylamine (1.00g., an excess) in refluxing ethanol (100 ml.) for 24 hours. Work-up as described in Example 4 yielded trans-4-isopropylamino-3,4-dihydro-2H-naphtho[1,2-b]pyran-3-ol D-(+)-hydrogen tartrate hydrate (0.30 g.) m.p. 108° - 110°.

Provenance & Evidence