7-methoxy-3,7-dimethyloctanal

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

Procedure: To a mixture of 10 g. of 7-methoxy-3,7-dimethyloctan-1-al, 17 g. of diethyl 3-ethoxycarbonyl-2-methylprop-2-enyl phosphonate (77% trans), and 150 ml. of dimethylformamide, under nitrogen, 0°, with stirring, is added sodium isopropanolate (prepared from 1.5 g. of sodium in 150 ml. of isopropanol). After addition is complete, the reaction is stirred for 18 hours at room temperature and then worked up by extraction with hexane to yield isopropyl 11-methoxy-3,7,11-trimethyldodeca-2,4-dienoate (mostly trans-2,trans-4), which can be chromatographed and distilled for further purification. To a mixture of 10 g After addition worked up by extraction with hexane

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 29.5 g of 3,7-dimethyl-7-methoxy-octanal and 42 g of diethylphosphono-α-methyl-crotonic acid methyl ester are dissolved in 100 ml of absolute benzene. To this solution there is added dropwise 4.1 g of sodium dissolved in 50 ml of absolute methanol. The mixture is stirred for 5 hours at 60°C., poured on to ice-water and extracted with diethyl ether. The ethereal solution is washed with water, then with aqueous sodium bicarbonate solution and once again with water, dried with sodium sulphate, filtered and concentrated on a rotary evaporator. After chromatography on a 30-fold amount of Kieselgel, using hexane/diethyl ether (9:1 parts by volume) as the eluant, there is obtained 11-methoxy-2,7,11-trimethyl-2,4-dodecadienoic acid methyl ester; boiling point 100°C/0.002 mmHg. extracted with diethyl ether The ethereal solution is washed with water with aqueous sodium bicarbonate solution and once again with water, dried with sodium sulphate filtered concentrated on a rotary evaporator

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

Procedure: 93.2 g. of 7-methoxycitronellal dissolved in 200 ml. of absolute diethyl ether are added dropwise with ice cooling to a suspension of 7.6 g. of lithium aluminum hydride in 500 ml. of absolute diethyl ether. Subsequently, the mixture is stirred for 30 minutes and decomposed in the cold by the addition of 100 ml. of aqueous ammonium chloride solution. The resulting mass is filtered through diatomaceous earth, the filtrate washed once with saturated aqueous ammonium chloride solution and once with saturated aqueous sodium chloride solution, dried over sodium sulfate and evaporated. The residue is distilled at 0.1 mmHg. There is obtained pure 3,7-dimethyl-7-methoxy-1-octanol of boiling point 87° C./0.1 mmHg; nD20 = 1.4456. decomposed in the cold by the addition of 100 ml The resulting mass is filtered through diatomaceous earth the filtrate washed once with saturated aqueous ammonium chloride solution and once with saturated aqueous sodium chloride solution dried over sodium sulfate evaporated The residue is distilled at 0.1 mmHg

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

Procedure: A process according to claim 1 which comprises the following steps (a) reacting citronellal with about 1-3 mols of dimethylamine, butylamine or ammonia per mol of citronellal at -5°C. to -25°C. (b) contacting the product of step (a) with methanol at -10°C. to +20°C. in the presence of 3.5-5 mols sulphuric acid per mol of citronellal used in step (a) and (c) neutralising the reaction mixture of step (b) with an aqueous solution of sodium hydroxide to produce methoxydihydrocitronellal. at -5°C. to -25°C. at -10°C. to +20°C.

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

Procedure: To a mixture of 10 g. of 7-methoxy-3,7-dimethyloctan-1-al, 17 g. of diethyl 3-ethoxycarbonyl-2-methylprop-2-enyl phosphonate (77% trans), and 150 ml. of dimethylformamide, under nitrogen, 0°, with stirring, is added sodium isopropanolate (prepared from 1.5 g. of sodium in 150 ml. of isopropanol). After addition is complete, the reaction is stirred for 18 hours at room temperature and then worked up by extraction with hexane to yield isopropyl 11-methoxy-3,7,11-trimethyldodeca-2,4-dienoate (mostly trans-2,trans-4), which can be chromatographed and distilled for further purification. To a mixture of 10 g After addition worked up by extraction with hexane