2-Methyl-2,7-diazabicyclo 4.1,0 hept-4-enes

Similarly, the regiospecific 1,3-dipolar cycloaddition reaction of 1-methyl-1,2-dihydropyridines 41 with cyanogen azide (50a) and selected organic azides 50c and 50g afforded 2-methyl-2,7-diazabicyclo[4.1.0]hept-4-enes 57, which can be elaborated to 1-methyl-l,2,5,6-tetrahydropyridylidene-2-cyanamide (58) and 1-methyl-2-piperidylidenes 59a-d (85CJC2362). 

A -methyl-9,10-ethanoanthracene-9(10ll)-propanamide (C20H21NO 23716-34-9) see Maprotiline [liJ-[ltt,5a,6(7J )]]-a-(l-methylethenyl)-7-oxo-3-phenyl-4-oxa-2,6-diazabicyclo[3.2.0]hept-2-ene-6-acetic acid diphe-nylmethyl ester... 

A suspension of 3,4-dihydroxy-5-methanesulfonyloxy-cyclohex-l-ene-l-carboxylic acid methyl ester (20.78 g, 78 mmol) in tetrahydrofuran (400 ml) at 0°C was treated with l,8-diazabicyclo[5.4.0]undec-7-ene (11.7 ml, 78 mmol) and was stirred at room temperature for 9 h at which time the reaction was complete. The reaction was evaporated and the crude residue was dissolved in CH2CI2 (200 ml) and was washed with saturated NaCI (300 ml). The aqueous phase was extracted with CH2CI2 (2 times 200 ml). The combined organic extracts were dried (MgS04), filtered, and evaporated. The crude product was purified on silica gel (ethyl acetate) to afford 5-hydroxy-7-oxa-bicyclo[4.1.0]hept-3-ene-3-carboxylic acid methyl ester (12 g, 90%) as a white solid. 

C22H30INO2, 2-Benzyl-1,2,3,4-tetrahydro-6,7-dimethoxy-2-methyl-1-isopropyl-isoquinolinium iodide, 45B, 284 C23H,7N02r 1-Isoquinolyl(phenyl)methyl benzoate, 45B, 285 C2 3H2 oBr2N2O5, Dimethyl 1,2-bis-(4-bromophenyl)-3,5-dimethyl-4-oxo-6,7-diazabicyclo[3.2.0]hept-2-ene-6,7-dicarboxylate, 38B, 297 C2 3H21N3O5, 4-Ethoxycarbonyl-5-methoxy-1-phenyl-3-(a-phthalimidoeth-yDpyrazole, 46B, 265... 

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