Processes for preparing 1,2-epoxy-1,2,3,4-tetrahydronaphthalenes

A process for the preparation of (1R,2S)-1,2-epoxy-1,2,3,4-tetrahydronaphthalene having the Formula (IA):

• ##STR28## which comprises the steps of a) hydrogenating the compound of Formula (II) to form cis-(1R,2S)-1,2-dihydroxy-1,2,3,4-tetrahydronaphthalene of Formula (V):
• ##STR29## b) reacting the compound of Formula (V) with an alkyl orthoalkanoate of Formula (VI) to form a mixture of dioxolane diastereoisomers of Formula (VII) and (VIIB):
• ##STR30## in which R is alkyl and R.sup.3 is H, alkyl or phenyl;
• c) reacting the mixture of dioxolane diastereoisomers of Formulae (VII) and (VIIB) with a halotrialkyl- or halotriarylsilane of Formula (XIV) to form a compound of Formula (IX):
• ##STR31## in which:
• R.sup.2 is alkyl or aryl;
• X is --Cl, --Br or --I;
• and
• R.sup.3 is as hereinbefore defined;
• d) reacting the compound of Formula (IX) with an alkali metal alkoxide to form (1R,2S)-1,2-epoxy-1,2,3,4-tetrahydronaphthalene having the Formula (IA).