Substituted methyl isopropyl cyclohexenones, organoleptic uses thereof and process for preparing same

Described is the genus of compounds defined according to the structure: wherein one of the dashed lines represents a carbon-carbon double bond and the other of the dashed lines represents a carbon-carbon single bond; wherein R4 represents methyl or ethyl; wherein one of the R1, R2 and R3 represents 2-methyl-1-propenyl or 2-methyl-1-propylidenyl; and the other of R1, R2 and R3 represent hydrogen; with the provisos that: (i) when the dashed line at the 3-4 position is a double bond, then R3 is hydrogen or 2-methyl-1-propenyl; (ii) when the dashed line at the 2-3 position is a double bond, then R2 is hydrogen or 2-methyl-1-propenyl; (iii) when R4 is ethyl, then R2 is methyl and the double bond is at the 2-3 position; and (iv) when R4 is methyl, then R2 is hydrogen; 2-methyl-1-propenyl or 2-methyl-1-propylidenyl; with the members of said genus being novel compounds when R4 is ethyl or when R4 is methyl and the double bond is at the 3-4 position or when R4 is methyl and the double bond is at the 2-3 position with R3 being hydrogen. The compounds of the genus defined according to the structure: are useful in augmenting or enhancing the aroma or taste of consumable materials including smoking tobacco compositions, smoking tobacco articles, perfume compositions, colognes and perfumed articles (e.g. solid or liquid anionic, cationic, nonionic or zwitterionic detergents, cosmetic powder compositions, fabric softener compositions and fabric softener articles). Also described is the novel process for preparing compounds defined according to the genus having the structure: by either dimerizing unsaturated ketones defined according to the structure: wherein one of the dashed lines is a carbon-carbon double bond and the other of the dashed lines is a carbon-carbon single bond and wherein R4' represents hydrogen or methyl in the presence of an appropriate catalyst such as an alkali metal hydroxide or an alkaline earth metal hydroxide catalyst, aluminum chloride, sulfuric acid or the like or by reaction of isobutyraldehyde and acetone or methyl ethyl ketone in the presence of an appropriate catalyst such as an alkali metal hydroxide or an alkaline earth metal hydroxide or aluminum chloride or the like.