2-Pentylpropane-1,3-diol

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

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

Procedure: An equimolar mixture of p-trifluoromethylbenzaldehyde and 2-pentylpropane-1,3-diol in toluene is boiled on a water separator with catalysis by p-toluenesulfonic acid. When the water separation is complete and after conventional work-up, p-(trans-5-n-pentyl-1,3-dioxan-2-yl)-trifluorotoluene, m.p. 44.3°, Δε=+12.9, is obtained. When the water separation

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

Procedure: 20.4 g of 5-n-octylthieno[2,3-b]thiophene-2-carbaldehyde (obtainable from 2-n-octylthieno[2,3-b]thiophene by Vilsmeyer formylation with phosphorus oxychloride/dimethylformamide) and 9.5 g of 2-n-pentylpropane-1,3-diol are dissolved in 150 ml of toluene, a pinch of toluenesulfonic acid is added, and the mixture is heated under a water separator until water is no longer separated off. The acid is washed out with sodium bicarbonate solution, the organic phase is dried over sodium sulfate, and the toluene is distilled off. The pure trans-2-(5-n-octylthieno[2,3-b]thien-2-yl)-5-n-pentyl-1,3-dioxane is obtained by repeated recrystallization from ethanol (17.5 g). the mixture is heated under a water is no longer separated off The acid is washed out with sodium bicarbonate solution the organic phase is dried over sodium sulfate the toluene is distilled off

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

Procedure: 20.4 g of 5-n-octylthieno[2,3-b]thiophene-2-carbaldehyde (obtainable from 2-n-octylthieno[2,3-b]thiophene by Vilsmeyer formylation with phosphorus oxychloride/dimethylformamide) and 9.5 g of 2-n-pentylpropane-1,3-diol are dissolved in 150 ml of toluene, a pinch of toluenesulfonic acid is added, and the mixture is heated under a water separator until water is no longer separated off. The acid is washed out with sodium bicarbonate solution, the organic phase is dried over sodium sulfate, and the toluene is distilled off. The pure trans-2-(5-n-octylthieno[2,3-b]thien-2-yl)-5-n-pentyl-1,3-dioxane is obtained by repeated recrystallization from ethanol (17.5 g). the mixture is heated under a water is no longer separated off The acid is washed out with sodium bicarbonate solution the organic phase is dried over sodium sulfate the toluene is distilled off

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

Procedure: A mixture of 2.00 g of trans-4-cyanocyclohexanecarboxaldehyde, 2.13 g of 2-pentyl-1,3-propanediol and 65 mg of p-toluenesulphonic acid in 100 ml of benzene was heated to reflux for 3 hours while gassing with argon and with separation of water in a round flask provided with a water separator and a reflux condenser. The mixture was subsequently treated with 3.0 g of potassium carbonate, stirred at room temperature for 16 hours, then filtered and the filtrate was concentrated. Recrystallization of the crystalline residue (4.1 g) from hexane at 0° C. gave 1.47 g (38%) of trans-4-(trans-5-pentyl-m-dioxan-2-yl)cyclohexanecarbonitrile as colourless crystals in a purity of 99.1%. After a further recrystallization from hexane at 0° C., the purity increased to 99.9%; m.p. (C--N) 45.6° C., cl.p. (N--I) 46.7° C. was heated to reflux for 3 hours while gassing with argon and with separation of water in a round flask provided with a water separator and a reflux condenser filtered the filtrate was concentrated Recrystallization of the crystalline residue (4.1 g) from hexane at 0° C.

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

Procedure: A mixture of 2-n-pentylpropane-1,3diol (8 g, 0.054 m), 4-carboxybenzaldehyde (8 g, 0.053 m), benzene (200 ml) and a catalytic amount of 4-toluenesulfonic acid was azeotropically refluxed until no more water was collected. The cold reaction mixture was washed with saturated NaHCO3 solution and water and then dried over anhydrous sodium sulfate. The solvent was evaporated and the residue was crystallized from ethanol to yield 4-(5-n-pentyl-1,3-dioxan-2-yl) benzoic acid (12 g, 80%) was collected The cold reaction mixture was washed with saturated NaHCO3 solution and water dried over anhydrous sodium sulfate The solvent was evaporated the residue was crystallized from ethanol

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

Procedure: A mixture of 2-n-pentylpropane-1,3diol (8 g, 0.054 m), 4-carboxybenzaldehyde (8 g, 0.053 m), benzene (200 ml) and a catalytic amount of 4-toluenesulfonic acid was azeotropically refluxed until no more water was collected. The cold reaction mixture was washed with saturated NaHCO3 solution and water and then dried over anhydrous sodium sulfate. The solvent was evaporated and the residue was crystallized from ethanol to yield 4-(5-n-pentyl-1,3-dioxan-2-yl) benzoic acid (12 g, 80%) was collected The cold reaction mixture was washed with saturated NaHCO3 solution and water dried over anhydrous sodium sulfate The solvent was evaporated the residue was crystallized from ethanol

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir: