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After stirring for 16 h MeOH (4 mL) was added and the mixture was warmed to 55° C. until no more gas was evolved. The mixture was concentrated to an oil, taken up in Et2O and washed successively with 2M phosphoric acid, saturated sodium bicarbonate, water and brine and then dried over MgSO4 and reconcentrated. The resulting oil was purified by high vacuum Kugelrohr at 150° C. to give pure alcohol (1,2,3,4-tetrahydronaphthalen-2-yl)methanol (2) (4.09 g) in 93% yield. To triphenylphosphine (10.179 g, 38.809 mmol) and imidazole (2.64 g, 38.809 mmol) in anhydrous benzene (175 mL) was added the iodine (8.60 g, 33.865 mmol) in benzene (75 mL) with rapid stirring followed by (2) in benzene (50 mL). After 3 h the solids were filtered off and the filtrate was reduced in vacuo to a volume of 50 mL to which was added hexane (200 mL). The resultant solids were filtered off and the filtrate was washed successively with water and brine, dried over MgSO4 and concentrated in vacuo. The resulting oil was purified by flash chromatography on silica with hexane to give pure 2-iodomethyl-1,2,3,4-tetrahydronaphthalene (3) (6.239 g) in 90% yield. To (3) (10.02 g, 36.85 mmol) and Cul (1.41 g, 7.37 mmol) in anhydrous THF (50 mL) at −78° C. under argon was added vinylmagnesium bromide (1M in THF, 73.70 mL, 73.70 mmol) slowly at a speed at which no color developed. This solution was allowed to warm to 0° C. and stirred for 6 h. The resulting mixture was recooled to −40° C. and quenched by the careful addition of 2M phosphoric acid (35 mL). This solution was diluted with 100 mL water and extracted with hexanes. The organic fractions were washed successively with water and brine, dried over MgSO4 and concentrated in vacuo. The resulting oil was purified by flash chromatography on silica with hexane to give 2-allyl-1,2,3,4-tetrahydronaphthalene (4) (5.618 g) in 88% yield. (4) (5.615 g, 32.645 mmol) and meta-chloroperbenzoic acid (m-CPBA) (14.08 g, 81.613 mmol) were stirred in anhydrous methylene chloride (50 mL) for 16 h. The solids were filtered off and potassium flouride KF (5.11 g, 88.142 mmol) was added and this mixture was stirred an additional hour. The solids were filtered off and the reaction was concentrated in vacuo. The resulting oil was purified by flash chromatography on silica with 5% ethyl acetate in hexane to give 2-(1,2,3,4-tetrahydronaphthalen-2-ylmethyl)oxirane (5) (5.41 g) in 88% yield. To (5) (1.626 g, 8.649 mmol) in a solution of acetone (20 mL) and water (5 mL) was added sodium azide (1.97 g, 30.271 mmol). This solution was warmed to 85° C. and stirred for 48 h. The solution was concentrated in vacuo and the residues were taken up in CHCl3 and washed successively with water and brine, dried over MgSO4 and concentrated in vacuo. The resulting oil was purified by flash chromatography on silica with 30% ethyl acetate in hexane to give pure 1-azido-3-(1,2,3,4-tetrahydronaphthalen-2-yl)propan-2-ol (6) (1.762 g) in 88% yield. A mixture of (6) (1.88 g, 8.140 mmol), triphenylphosphine (2.67 g, 10.173 mmol), phthalimide (1.50 g, 10.173 mmol), diethyl azodicarboxylate (DEAD) (1.77 g, 10.173 mmol) were stirred in anhydrous THF (50 mL) for 4 h. This solution was concentrated in vacuo, taken up in a solution of hexane (25 mL) and ether (25 mL) and stirred for 16 h. The solids were filtered off and the filtrate was concentrated in vacuo. The resulting oil was purified by flash chromatography on silica with 20% ethyl acetate in hexane to give 2-[1-azidomethyl-2-(1,2,3,4-tetrahydronaphthalen-2-yl)ethyl]isoindole-1,3-dione (7) (2.487 g) contaminated with a small amount of impurity which was carried on without further purification. A mixture of (7) (3.93 g, 10.917 mmol) and hydrazine (0.680 mL, 21.833 mmol) were heated in ethanol (60 mL) at reflux for 16 h. The solids were filtered off and the filtrate was concentrated in vacuo. The residues were purified by flash chromatography on silica with 5% MeOH in CH2Cl2 to give 1-azidomethyl-2-(1,2,3,4-tetrahydronaphthalen-2-yl)ethylamine (8) (2.057 g) in 88% yield. A mixture of (8) (2.056 g, 8.940 mmol) and 10% palladium on carbon (0.260 g) were stirred in MeOH (30 mL) under 1 atmosphere of hydrogen for 16 h. The solids were filtered off and the filtrate was concentrated in vacuo. The residues were purified by flash chromatography on silica with 10% ammonia saturated MeOH in CH2Cl2 to give 3-(1,2,3,4-tetrahydro-naphthalen-2-yl)propane-1,2-dione (9) (1.557 g) in 85% yield. A mixture of (9) (0.590 g, 2.892 mmol) and methanesulfonic acid (0.980 mL, 14.460 mmol) were heated in triethylorthoformate (10 mL) at 105° C. 3 h. The reaction was concentrated in vacuo and the solids were filtered off. Subsequent recrystalization of these solids from a mixture of MeOH and ether gave pure 4(5)-(1,2,3,4-tetrahydronaphthalen-2-ylmethyl)-4,5-dihydro-1H-imidazole, methane sulfonic acid salt (I) (0.435 g) in 48% yield.

1. customwas carried on without further purification
2. temperatureat reflux for 16 h
3. filtrationThe solids were filtered off
4. concentrationthe filtrate was concentrated in vacuo
5. customThe residues were purified by flash chromatography on silica with 5% MeOH in CH2Cl2