GB796129A - Polyalkylindane derivatives and process for manufacturing the same - Google Patents

Abstract

The invention comprises carbonyl derivatives of polyalkyl indanes in which 4-6 of the hydrogen atoms of the five-membered ring are substituted by alkyl groups containing 1-3 carbon atoms and a carbonyl group containing 1-3 carbon atoms is substituted on the benzene ring. Preferred compounds also contain an alkyl group having 1-3 carbon atoms substituted on the benzene ring. The compounds are prepared by introducing a formyl, acetyl or propionyl group into the corresponding polyalkylindanes, which are prepared by the process described in Specification 796,130 (i.e. by the reaction of styrene hydrocarbons with alkenes in the presence of a catalyst). The formyl compounds may be prepared by introducing a chloromethyl group into the polyalkylindane by reaction thereof with paraformaldehyde and hydrogen chloride in the presence of zinc chloride as a catalyst, and then converting the chloromethyl group into a formyl group by reaction with (a) hexamethylene tetramine in aqueous acetic acid or (b) the sodium salt of 2-nitropropane in ethanol. alternatively the polyalkylindane may be treated by the Gattermann-Koch method to introduce the formyl group. The acetyl and propionyl compounds may be prepared by reacting the polyalkylindane with an acetyl or propionyl halide or with acetic or propionic acid anhydride in the presence of a FriedelCrafts catalyst, such as aluminium chloride. The compounds are used as musk odorants and the intensity of the odour increases with the number of alkyl substitutents in the fivemembered ring. In examples: (1) p-a -dimethylstyrene is reacted with tetramethylethene (or 2:3-dimethylbutene-1) in a mixture of acetic and sulphuric acids to give 1 : 1 : 2 : 2 : 3 : 3 : 5-heptamethylindane which is reacted with acetyl or propionyl chloride in the presence of aluminium chloride to give acetyl- or propionyl-1: 1 : 2 : 2 : 3 : 3 : 5-heptamethyl-indane; (2) as in (1) but starting with p-ethyl-a -methylstyrene, acetyl - 1 : 1 : 2 : 2 : 3 : 3 - hexamethyl-5-ethyl-indane is obtained; (3) 1 : 1 : 2 : 3 : 3 : 5-hexamethylindane is obtained as in (1) but using trimethylethene, then reacted with paraformaldehyde, hydrogen chloride and zinc chloride to give 6-chloromethyl-1 : 1 : 2 : 3 : 3 : 5-hexamethylindane which is treated with a mixture of sodium hydroxide, 2-nitropropane and ethanol to give 6-formyl-1 : 1 : 2 : 3 : 3 : 5-hexamethylindane; (4) 1 : 1 : 2 : 2 : 3 : 3 : 5-heotamethyl-indane is treated as in (3) to give the chloromethyl compound which is reacted with hexamethylenetetramine in aqueous acetic acid to give 6-formyl-1 : 1 : 2 : 2 : 3 : 3 : 5-heptamethylindane. In Table the following additional compounds are specified: acetyl-1 : 2 : 3 : 3 : 5-or -1 : 1 : 3 : 3 : 5- or 1 : 1 : 2 : 3 : 3-pentamethylindane, acetyl - 1 : 1 : 3 : 5 - tetramethyl - 3 - ethyl-or -isopropyl-indane, acetyl-1 : 1 : 5-trimethyl - 3 : 3 - diethyl - indane, acetyl - 1 : 1 : 3 : 3 - tetramethyl - 5 - ethyl - indane, acetyl - 1 : 1 : 3 : 3 : 3 : 5 - or 1 : 1 : 2 : 2 : 3 : 3-hexamethyl-indane, acetyl-1 : 1 : 2 : 3 : 5-pentamethyl - 3 - ethyl - indane, acetyl - 1 : 1 : 2 : 3 : 3-pentamethyl - 5 - ethyl - indane, acetyl - 1 : 1 : 3 : 3 : 5 - pentamethyl - 2 - ethyl - indane, a mixture of acetyl-1 : 1 : 2 : 2 : 3 : 5-hexamethyl-3 - ethyl - indane and acetyl - 1 : 1 : 2 : 3 : 3 : 5-hexamethyl - 2 8 ethyl - indane, acetyl - 1 : 1 : 3 : 3 - tetramethylindane and 6 - formyl-1 : 1 : 2 : 3 : 3-pentamethylindane.