dibutyl carbonate

Conditions: temp:5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The operation was performed for 80 hours in the same apparatuses and procedure as in Example 1 except that butyl allophanate was cooled to 5° C. to deposit in a settling vessel equipped in a lower portion of condenser of distillation column 18 and only butanol was returned to reactor 1 via conduit pipe 22. But, in order to remove butyl allophanate, procedures to withdraw butyl allophanate from the settling vessel every one hour and filter out it from butanol became necessary. The feed rate of urea in a steady state was 73.3 mol/hr, whereas the production rate of dibutyl carbonate to be obtained via reaction liquid withdrawing pipe 14 was 71.1 mol/hr (97.0 mol % to fed urea). was returned to reactor But, in order to remove butyl allophanate, procedures to withdraw butyl allophanate from the settling vessel every one hour filter out it from butanol

Conditions: temp:5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The operation was performed for 80 hours in the same apparatuses and procedure as in Example 1 except that butyl allophanate was cooled to 5° C. to deposit in a settling vessel equipped in a lower portion of condenser of distillation column 18 and only butanol was returned to reactor 1 via conduit pipe 22. But, in order to remove butyl allophanate, procedures to withdraw butyl allophanate from the settling vessel every one hour and filter out it from butanol became necessary. The feed rate of urea in a steady state was 73.3 mol/hr, whereas the production rate of dibutyl carbonate to be obtained via reaction liquid withdrawing pipe 14 was 71.1 mol/hr (97.0 mol % to fed urea). was returned to reactor But, in order to remove butyl allophanate, procedures to withdraw butyl allophanate from the settling vessel every one hour filter out it from butanol

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

Procedure: A mixture of 3-hydroxy-3-isopropylaminomethyl-3,4-dihydro-2H-1,5-benzodioxepin (11.85 g.; 50 millimoles), prepared as described in Example 1, and dibutyl carbonate (13.1 g.) with a small piece of metallic sodium is heated in an oil bath. The temperature then is slowly raised to 170° C. with removal of butanol. Finally, the mixture is heated between 170°-200° C. with removal of excess dibutyl carbonate. The cooled reaction product is dissolved in benzene, washed with water, dried over sodium sulfate, and the solvent evaporated to give 3'-isopropyl-3,4-dihydro-2H-1,5-benzodioxepin-3-spiro-5'-oxazolidin-2'-one, m.p. 121°-122° C. prepared is heated in an oil bath The cooled reaction product washed with water dried over sodium sulfate the solvent evaporated

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

Procedure: A mixture of 3-hydroxy-3-isopropylaminomethyl-3,4-dihydro-2H-1,5-benzodioxepin (11.85 g.; 50 millimoles), prepared as described in Example 1, and dibutyl carbonate (13.1 g.) with a small piece of metallic sodium is heated in an oil bath. The temperature then is slowly raised to 170° C. with removal of butanol. Finally, the mixture is heated between 170°-200° C. with removal of excess dibutyl carbonate. The cooled reaction product is dissolved in benzene, washed with water, dried over sodium sulfate, and the solvent evaporated to give 3'-isopropyl-3,4-dihydro-2H-1,5-benzodioxepin-3-spiro-5'-oxazolidin-2'-one, m.p. 121°-122° C. prepared is heated in an oil bath The cooled reaction product washed with water dried over sodium sulfate the solvent evaporated

Conditions: temp:85.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 160 cc Parr autoclave was charged with 2.22 g (0.03 mol) butanol, 6.9 g (0.035 mol) N-cyclohexyl-N',N',N",N"-tetramethylguanidine and 30 mL CH3CN. The autoclave was attached to a pressure head and at room temperature with stirring was added 160 psig carbon dioxide. Addition of CO2 resulted in an exothermic reaction with a rise in temperature to ca. 40° C. Into a Fischer-Porter bottle was added 8.33 g (0.09 mol) butyl chloride in 10 mL CH3CN. This mixture was attached to a pressure head and 80 psig carbon dioxide was added above the solution. After 1 h the butyl chloride solution was added all at once under 80 psig CO2 to the pre-formed carbamate anion solution generated in the autoclave. After addition the pressure was raised to 160 psig with carbon dioxide and the reaction mixture was warmed to 85° C. for 16 h. After this time the reaction mixture was allowed to cool to room temperature and then the pressure was released. An aliquot was taken, diluted with diethyl ether, Cl-+HCyTMG filtered off and by G.C. analysis a 73% yield of dibutyl carbonate was calculated. Oil 1H NMR (CDCl3) 4.14(t, J=6.6 Hz, 4H), 1.66 (m, 4H), 1.41 (m, 4H), 0.94 (t, J=7.3 Hz, 6H). 13C{1H} NMR (CDCl3) 155.9, 68.2, 31.2, 19.4, 14.1. IR (film) 1746, 1260; MS (FAB) m/z=175 (MH+). was attached to a pressure head and at room temperature resulted in an exothermic reaction with a rise in temperature to ca. 40° C was added above the solution After addition the pressure to cool to room temperature filtered off and by G.C

Conditions: temp:85.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 160 cc Parr autoclave was charged with 2.22 g (0.03 mol) butanol, 6.9 g (0.035 mol) N-cyclohexyl-N',N',N",N"-tetramethylguanidine and 30 mL CH3CN. The autoclave was attached to a pressure head and at room temperature with stirring was added 160 psig carbon dioxide. Addition of CO2 resulted in an exothermic reaction with a rise in temperature to ca. 40° C. Into a Fischer-Porter bottle was added 8.33 g (0.09 mol) butyl chloride in 10 mL CH3CN. This mixture was attached to a pressure head and 80 psig carbon dioxide was added above the solution. After 1 h the butyl chloride solution was added all at once under 80 psig CO2 to the pre-formed carbamate anion solution generated in the autoclave. After addition the pressure was raised to 160 psig with carbon dioxide and the reaction mixture was warmed to 85° C. for 16 h. After this time the reaction mixture was allowed to cool to room temperature and then the pressure was released. An aliquot was taken, diluted with diethyl ether, Cl-+HCyTMG filtered off and by G.C. analysis a 73% yield of dibutyl carbonate was calculated. Oil 1H NMR (CDCl3) 4.14(t, J=6.6 Hz, 4H), 1.66 (m, 4H), 1.41 (m, 4H), 0.94 (t, J=7.3 Hz, 6H). 13C{1H} NMR (CDCl3) 155.9, 68.2, 31.2, 19.4, 14.1. IR (film) 1746, 1260; MS (FAB) m/z=175 (MH+). was attached to a pressure head and at room temperature resulted in an exothermic reaction with a rise in temperature to ca. 40° C was added above the solution After addition the pressure to cool to room temperature filtered off and by G.C

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

Procedure: An equimolar mixture of dibutylcarbonate and 3-amino-1,2-propanediol was allowed to react resulting in formation of butyl 2,3-dihydroxypropylcarbamate. to react

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

Procedure: An equimolar mixture of dibutylcarbonate and 3-amino-1,2-propanediol was allowed to react resulting in formation of butyl 2,3-dihydroxypropylcarbamate. to react

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

Procedure: After 150 minutes of starting of the reaction, the reflux ratio was set to 0.2 and unreacted phenol and dibutyl carbonate were mainly distilled out in a reflux ratio of 0.2 by lowering gradually the reaction pressure from atmospheric pressure to 450 mmHg. After 40 minutes, unreacted phenol and dibutyl carbonate were almost distilled out. At this time, the bottom section temperature was 205° C. Then, dibutyl carbonate due to disproportionation was mainly distilled out by further lowering gradually the reaction pressure to 100 mmHg. After 2 hours of setting the reflux ratio to 0.2, the reaction was completed. At this time, the reaction liquid was analyzed. At this time, the bottom section temperature was 207° C. The distilled-out liquid contained 668 g of dibutyl carbonate, 774 g of phenol and 18 g of butanol. The bottom liquid was further distilled in order to remove the catalyst, whereby 133 g of diphenyl carbonate was obtained as the distillate. After 150 minutes of starting of the reaction were mainly distilled out in a reflux ratio of 0.2 the reaction pressure from atmospheric pressure to 450 mmHg unreacted phenol and dibutyl carbonate were almost distilled out was 205° C Then, dibutyl carbonate due to disproportionation was mainly distilled out the reaction pressure to 100 mmHg After 2 hours of setting At this time, the reaction liquid was 207° C The bottom liquid was further distilled in order to remove the catalyst

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

Procedure: After 150 minutes of starting of the reaction, the reflux ratio was set to 0.2 and unreacted phenol and dibutyl carbonate were mainly distilled out in a reflux ratio of 0.2 by lowering gradually the reaction pressure from atmospheric pressure to 450 mmHg. After 40 minutes, unreacted phenol and dibutyl carbonate were almost distilled out. At this time, the bottom section temperature was 205° C. Then, dibutyl carbonate due to disproportionation was mainly distilled out by further lowering gradually the reaction pressure to 100 mmHg. After 2 hours of setting the reflux ratio to 0.2, the reaction was completed. At this time, the reaction liquid was analyzed. At this time, the bottom section temperature was 207° C. The distilled-out liquid contained 668 g of dibutyl carbonate, 774 g of phenol and 18 g of butanol. The bottom liquid was further distilled in order to remove the catalyst, whereby 133 g of diphenyl carbonate was obtained as the distillate. After 150 minutes of starting of the reaction were mainly distilled out in a reflux ratio of 0.2 the reaction pressure from atmospheric pressure to 450 mmHg unreacted phenol and dibutyl carbonate were almost distilled out was 205° C Then, dibutyl carbonate due to disproportionation was mainly distilled out the reaction pressure to 100 mmHg After 2 hours of setting At this time, the reaction liquid was 207° C The bottom liquid was further distilled in order to remove the catalyst

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

Procedure: 1795 g of the top section liquid obtained above containing 862 g of dibutyl carbonate, 932 g of phenol and 1 g of butyl carbamate and 16.8 g of titanium tetrabutoxide were charged into a round bottom flask of capacity 5 L in which a distillation column made from glass provided with a vacuum jacket (filled Sulzer Labopacking, inner diameter 50mmφ, height of filling portion 1100 mm) was connected to an upper portion thereof. The contents in the flask were heated with a mantle heater while stirring at 300 rpm with a mechanical stirrer. When the bottom section temperature became 191° C., reflux was started. All reflux was performed for 10 minutes after starting of reflux and then distillation-out was started in a reflux ratio of 30. The starting time of distillation-out was regarded as starting of the reaction. The yield (mol %) of butyl phenyl carbonate based on charged dibutyl carbonate was analyzed by gas chromatography. The yield was 12.3% in the reaction for 30 min., 18.6% in the reaction for 60 min., 22.5% in the reaction for 90 min., 27.4% in the reaction for 120 min., and 30.0% in the reaction for 150 min. The amount of distilled-out liquid was 131 g and the distilled-out liquid contained 128 g of butanol and 3 g of phenol. The bottom section temperature was 192° C. at the starting time of distillation-out and 197° C. after 150 minutes of starting of the reaction. 1795 g of the top section liquid obtained were charged into a round bottom flask of capacity 5 L in which a distillation column provided with a vacuum jacket (filled Sulzer Labopacking, inner diameter 50mmφ, height of filling portion 1100 mm) The contents in the flask were heated with a mantle heater became 191° C. reflux of reflux distillation-out The starting time of distillation-out as starting of the reaction

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

Procedure: A liquid containing 42.6% by weight (hereinafter, “wt %”) of dibutyl carbonate, 11.4 wt % of butyl carbamate and 46.0 wt % of phenol was fed at the rate of 300 g/hr at 100° C. to a center portion of a distillation column made from glass provided with a vacuum jacket (filled Sulzer Labopacking, inner diameter 50 mmφ, height of filling portion: concentration portion 550 mm, recovery portion 550 mm) and the continuous distillation was performed under a top section pressure of 20 mmHg in the distillation column. The distillation column was operated in a reflux ratio of 3 and adjusted to distill out 265 g/hr of a distillate from the top section and thus steady state was maintained. In the distillation, a liquid containing 48.2 wt % of dibutyl carbonate and 51.8 wt % of phenol was obtained as a distillate of the top section. Butyl carbamate content in the liquid thus obtained was below 0.05 wt %. A liquid containing 98.0 wt % of butyl carbamate and 2.0 wt % of phenol was obtained at the rate of 35 g/hr from the bottom section. Dibutyl carbonate content in the liquid thus obtained was below 0.05 wt %. In this distillation, the top section temperature was 94° C. and the bottom section temperature was 118° C. was obtained at the rate of 35 g/hr from the bottom section