N,N-dimethylmethanamine;sulfur trioxide

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

Procedure: To a mixture of water (25.0) and L-ascorbic acid (2.0g, 11.5 millimoles) was added barium hydroxide octahydrate with stirring until the solution had pH 10.5. The mixture was warmed to 70°, and trimethylamine-sulfur trioxide (2.4g, 1.5 equivalent) was added. Solid barium hydroxide octahydrate was added intermittently to maintain the reaction pH at 10.5. A total of 5g of barium hydroxide octahydrate was used in the reaction to this point. After 30 minutes the reaction was complete as indicated by thin-layer chromatography. The mixture was cooled and a saturated aqueous solution of barium hydroxide (1-2 ml) was added to adjust the solution pH to 12.5. Nitrogen was passed through the mixture at 70° to expel trimethylamine. The solution was diluted with water (100 ml) and neutralized with aqueous sulfuric acid. Insoluble barium sulfate was removed by filtration, and the filtrate decolorized with charcoal and evaporated to a small volume (30 ml). Addition of methanol (30 ml) followed by cooling gave 3.94 g (80%) of barium L-ascorbate 2-sulfate dihydrate with m.p. 234°-40°. The mixture was warmed to 70° to maintain the reaction pH at 10.5 The mixture was cooled was passed through the mixture at 70° Insoluble barium sulfate was removed by filtration evaporated to a small volume (30 ml) Addition of methanol (30 ml) by cooling

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

Procedure: A Fischer-Porter bottle was charged with 0.55 g (4.2 mmol) of octyl amine, 0.99 g of P1 tBu (3 mmol), 25 mL of acetonitrile and 130 mg (0.84 mmol) of tridecane as an internal standard. The bottle was pressurized to 80 psig with carbon dioxide and the solution was stirred for 30 min. at room temperature. A second Ficher-Porter bottle was charged with 0.65 g (4.7 mmol) of sulfur trioxide trimethylamine adduct (SO3 -NMe3) and 20 mL of acetonitrile then pressurized to 80 psig with CO2. The two solutions were cooled to 0° C. in an ice bath for 10 min after which time the octyl carbamate solution was added rapidly to the SO3 -NMe3 suspension. An aliquot was taken after five minutes and diluted with diethyl ether prior to G.C. analysis which indicated a yield of 11% octyl isocyanate. Further monitoring of the reaction progress over 48 hrs gave a maximum yield of 27% octyl isocyanate. An aliquot was taken after five minutes

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

Procedure: To a mixture of water (25.0) and L-ascorbic acid (2.0g, 11.5 millimoles) was added barium hydroxide octahydrate with stirring until the solution had pH 10.5. The mixture was warmed to 70°, and trimethylamine-sulfur trioxide (2.4g, 1.5 equivalent) was added. Solid barium hydroxide octahydrate was added intermittently to maintain the reaction pH at 10.5. A total of 5g of barium hydroxide octahydrate was used in the reaction to this point. After 30 minutes the reaction was complete as indicated by thin-layer chromatography. The mixture was cooled and a saturated aqueous solution of barium hydroxide (1-2 ml) was added to adjust the solution pH to 12.5. Nitrogen was passed through the mixture at 70° to expel trimethylamine. The solution was diluted with water (100 ml) and neutralized with aqueous sulfuric acid. Insoluble barium sulfate was removed by filtration, and the filtrate decolorized with charcoal and evaporated to a small volume (30 ml). Addition of methanol (30 ml) followed by cooling gave 3.94 g (80%) of barium L-ascorbate 2-sulfate dihydrate with m.p. 234°-40°. The mixture was warmed to 70° to maintain the reaction pH at 10.5 The mixture was cooled was passed through the mixture at 70° Insoluble barium sulfate was removed by filtration evaporated to a small volume (30 ml) Addition of methanol (30 ml) by cooling

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

Procedure: A Fischer-Porter bottle was charged with 0.55 g (4.2 mmol) of octyl amine, 0.99 g of P1 tBu (3 mmol), 25 mL of acetonitrile and 130 mg (0.84 mmol) of tridecane as an internal standard. The bottle was pressurized to 80 psig with carbon dioxide and the solution was stirred for 30 min. at room temperature. A second Ficher-Porter bottle was charged with 0.65 g (4.7 mmol) of sulfur trioxide trimethylamine adduct (SO3 -NMe3) and 20 mL of acetonitrile then pressurized to 80 psig with CO2. The two solutions were cooled to 0° C. in an ice bath for 10 min after which time the octyl carbamate solution was added rapidly to the SO3 -NMe3 suspension. An aliquot was taken after five minutes and diluted with diethyl ether prior to G.C. analysis which indicated a yield of 11% octyl isocyanate. Further monitoring of the reaction progress over 48 hrs gave a maximum yield of 27% octyl isocyanate. An aliquot was taken after five minutes