Total synthesis of 1RS,4SR,5RS-4-(4,8-dimethyl)-5-hydroxy-7-nonen-1-yl)-4-methyl-3,8-dioxabicyclo[3.2.1]octane-1-acetic acid

Claim 1

The process for the preparation of a compound of the formula ##STR3## which comprises reacting a compound of the formula ##STR4## first with potassium acetate and then with diazomethane to form a compound of the formula ##STR5## reacting the ketone with a compound of the formula (C.sub.6 H.sub.5).sub.3 P═CH.sub.2 to form a compound of the formula ##STR6## hydrolyzing the ester with a base to form a compound of the formula ##STR7## oxidizing the hydroxy acid with a first oxidizing agent and treating the resulting product with an alcohol in the presence of an acid to form a compound of the formula ##STR8## reacting the bis-hydroxymethyl compound with an alcohol in the presence of acid to form a compound of the formula ##STR9## reacting the hydroxy ester with a second oxidizing agent, reacting the product formed with ethylene glycol and hydrolyzing the ester with a base to form a compound of the formula ##STR10## reacting the acid with borane-THF and the product formed with methanesulfonyl chloride to form a compound of the formula ##STR11## reacting the mesylate with a compound of the formula ##STR12## and hydrolyzing the ester to form a compound of the formula ##STR13## reacting the acid with 3-methyl-2-butenyl lithium, reacting the ketone formed with a reducing agent, hydrolyzing the hydroxy acetal with aqueous hydrochloric acid and esterifying the hydroxy compound with an esterifying agent to form a compound of the formula ##STR14## reacting the aldehyde with a compound of the formula (C.sub.6 H.sub.5).sub.3 P═CH.sub.2 reacting the product formed first with borane-THF followed by treatment with an alkali metal hydroxide and hydrogen peroxide, oxidizing the product formed with a third oxidizing agent, hydrolyzing the ester with a base and treating the salt formed with a mineral acid, wherein R is a lower alkanoyl group having 2-6 carbon atoms, and Ms is a mesyl group.