3-(2-oxocyclohexyl)propanal

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The title compound 1 was prepared in the following way. ##STR18## Isobutyraldohyde was alkylated with methyl vinyl ketone via its pyrrolidine enamine, cyclized in acid, and then hydrogenated to give 4,4-dimethylcyclohexanone (2). Ketone 2 was alkylated with acrolein via its morpholline enamine then hydrolyzed to give 3-(2-oxocyclohexyl)propanal (3). Crude 3 was then purified through its diketal, cyclized in 7 N hydrochloric acid, and esterified to give 7,7-dimethylbicyclo(3.3.1)nonan-9-one-2-yl pivalate (4). Kettalization of 4 followed by alkaline hydrolysis, CrO,--pyridine oxidation, and alkylation with iodomethane and potassium t-butoxide yielded 3,3,7,7-tetramothyl-9,9-ethylenedioxybicyclo(3.3.1)nonan2one (5). When various attempts of Wolff-Kishner reduction failed, 5 was reduced to alcohol with lithium--ammonia then mesylated to give 3,3,7,7-tetramethyl-9,9-ethylenedioxybicyclo(3.3.1)nonan-2-exo-yl methanesulfonae (6). Lithium--ammonia reduction of 6 followed by acid hydrolysis afforded the title compound 1.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The title compound 1 was prepared in the following way. ##STR18## Isobutyraldohyde was alkylated with methyl vinyl ketone via its pyrrolidine enamine, cyclized in acid, and then hydrogenated to give 4,4-dimethylcyclohexanone (2). Ketone 2 was alkylated with acrolein via its morpholline enamine then hydrolyzed to give 3-(2-oxocyclohexyl)propanal (3). Crude 3 was then purified through its diketal, cyclized in 7 N hydrochloric acid, and esterified to give 7,7-dimethylbicyclo(3.3.1)nonan-9-one-2-yl pivalate (4). Kettalization of 4 followed by alkaline hydrolysis, CrO,--pyridine oxidation, and alkylation with iodomethane and potassium t-butoxide yielded 3,3,7,7-tetramothyl-9,9-ethylenedioxybicyclo(3.3.1)nonan2one (5). When various attempts of Wolff-Kishner reduction failed, 5 was reduced to alcohol with lithium--ammonia then mesylated to give 3,3,7,7-tetramethyl-9,9-ethylenedioxybicyclo(3.3.1)nonan-2-exo-yl methanesulfonae (6). Lithium--ammonia reduction of 6 followed by acid hydrolysis afforded the title compound 1.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The title compound 1 was prepared in the following way. ##STR18## Isobutyraldohyde was alkylated with methyl vinyl ketone via its pyrrolidine enamine, cyclized in acid, and then hydrogenated to give 4,4-dimethylcyclohexanone (2). Ketone 2 was alkylated with acrolein via its morpholline enamine then hydrolyzed to give 3-(2-oxocyclohexyl)propanal (3). Crude 3 was then purified through its diketal, cyclized in 7 N hydrochloric acid, and esterified to give 7,7-dimethylbicyclo(3.3.1)nonan-9-one-2-yl pivalate (4). Kettalization of 4 followed by alkaline hydrolysis, CrO,--pyridine oxidation, and alkylation with iodomethane and potassium t-butoxide yielded 3,3,7,7-tetramothyl-9,9-ethylenedioxybicyclo(3.3.1)nonan2one (5). When various attempts of Wolff-Kishner reduction failed, 5 was reduced to alcohol with lithium--ammonia then mesylated to give 3,3,7,7-tetramethyl-9,9-ethylenedioxybicyclo(3.3.1)nonan-2-exo-yl methanesulfonae (6). Lithium--ammonia reduction of 6 followed by acid hydrolysis afforded the title compound 1.