Syntheses of spiro[2,3-dihydro-4H-l-benzopyran-4,l'-cyclohexan]-2-one derivatives by reaction sequences including a radical reaction and a total synthesis of (±)-lycoramine (2) are described. Radical reactions (BuaSnH, AIBN) of 1-[(l'-cyclohexenylmethyl)oxy] -2-halobenzenes 23b-d in boiling benzene gave the corresponding spiro[2,3-dihydrobenzofuran-3,l'-cyclohexanes] 26a,b in good yields, whereas the reaction of l-(l'-cyclohexenylethoxy)-2-bromobenzene (25) under similar conditions afforded a mixture of spiro[2,3-dihydro-4H-l-benzopyran-4,l,-cyclohexane] 27 and benzoxepin 28. Furthermore, the radical reaction of ethyl 2-[(2'-bromoaryl)oxy] -1-cyclohexenylacetate 37a produced ethyl 2-spiro[2,3-dihydrobenzofuran-3,l'-cyclohexane]carboxylate 38 in good yield. Compound 38 was converted to spiro[2,3-dihydro-4ff-l-benzopyran-4,l'-cyclohexane]-2,4'-dione 40 by treatment with Sml2 and then with 3 N HC1. Spiro[2,3-dihydro-4H-l-benzopyran-4,l'-cyclohexane]-2,4'-dione 40 was transformed to (±)-lycoramine (2) in four steps and 43% overall yield.

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