2-(1-hydroxypentyl)cyclopentan-1-one

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

Conditions: temp:15.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 100 mL four-necked flask was charged with 16.6 g (0.92 mol) of water and 0.16 g (0.004 mol) of sodium hydroxide. After cooling the contents of the flask to 15° C. under stirring, a mixed solution containing 61.3 g (0.71 mol) of valeraldehyde (acid value: 1.5 mg-KOH/g) and 237.8 g (2.83 mol) of cyclopentanone, and 36.0 g of a sodium hydroxide aqueous solution (concentration of sodium hydroxide: 0.36% by mass) were added dropwise into the flask over 6 h. While dropping, the resulting reaction mixture was withdrawn from the flask at a rate 1.4 times the dropping rate, and introduced into a dropping funnel (separator) to separate the reaction mixture into an organic layer and a water layer. The water layer separated as a lower layer of the reaction mixture was returned to the flask. Whereas, the organic layer separated as an upper layer of the reaction mixture was collected every one hour, and each part of the organic layer collected every one hour was subjected to gas chromatography. After completion of the dropping, the reaction mixture in the flask was separated into the respective layers, and each of the thus separated organic and water layers was analyzed by gas chromatography. As a result, it was confirmed that the organic layer contained 3.06 g (0.036 mol) of valeraldehyde, 106.5 g (0.63 mol) of 2-(1-hydroxy-n-pentyl)cyclopentanone and 2.13 g (0.014 mol) of pentylidene cyclopentanone (conversion rate of valeraldehyde: 95.0%; yield: 89.9%). were added dropwise into the flask over 6 h the resulting reaction mixture was withdrawn from the flask at a rate 1.4 times the dropping rate introduced into a dropping funnel (separator) to separate the reaction mixture into an organic layer The water layer separated as a lower layer of the reaction mixture Whereas, the organic layer separated as an upper layer of the reaction mixture was collected every one hour each part of the organic layer collected every one hour After completion of the dropping, the reaction mixture in the flask was separated into the respective layers

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

Conditions: temp:15.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 100 mL four-necked flask was charged with 16.6 g (0.92 mol) of water and 0.16 g (0.004 mol) of sodium hydroxide. After cooling the contents of the flask to 15° C. under stirring, a mixed solution containing 61.3 g (0.71 mol) of valeraldehyde (acid value: 1.5 mg-KOH/g) and 237.8 g (2.83 mol) of cyclopentanone, and 36.0 g of a sodium hydroxide aqueous solution (concentration of sodium hydroxide: 0.36% by mass) were added dropwise into the flask over 6 h. While dropping, the resulting reaction mixture was withdrawn from the flask at a rate 1.4 times the dropping rate, and introduced into a dropping funnel (separator) to separate the reaction mixture into an organic layer and a water layer. The water layer separated as a lower layer of the reaction mixture was returned to the flask. Whereas, the organic layer separated as an upper layer of the reaction mixture was collected every one hour, and each part of the organic layer collected every one hour was subjected to gas chromatography. After completion of the dropping, the reaction mixture in the flask was separated into the respective layers, and each of the thus separated organic and water layers was analyzed by gas chromatography. As a result, it was confirmed that the organic layer contained 3.06 g (0.036 mol) of valeraldehyde, 106.5 g (0.63 mol) of 2-(1-hydroxy-n-pentyl)cyclopentanone and 2.13 g (0.014 mol) of pentylidene cyclopentanone (conversion rate of valeraldehyde: 95.0%; yield: 89.9%). were added dropwise into the flask over 6 h the resulting reaction mixture was withdrawn from the flask at a rate 1.4 times the dropping rate introduced into a dropping funnel (separator) to separate the reaction mixture into an organic layer The water layer separated as a lower layer of the reaction mixture Whereas, the organic layer separated as an upper layer of the reaction mixture was collected every one hour each part of the organic layer collected every one hour After completion of the dropping, the reaction mixture in the flask was separated into the respective layers

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

Procedure: In a 50 ml four-neck flask fitted with a thermometer, a reflux condenser and a stirrer were placed 2-(1-hydroxypentyl)cyclopentanone (20 g) synthesized in Reference Example 1, N-iodosuccinimide (0.1 g) and toluene (10 ml), and water was removed under refluxing, followed by 4 hours of the reaction at 150° C. The reaction mixture was washed with water and the layers were separated from each other. Further, the resulting organic layer was washed with saturated brine and separated. The organic layer was evaporated on a rotary evaporator under reduced pressure to recover toluene, whereby a crude product was obtained. The product was distilled using a Claisen distillation apparatus to obtain 15.3 g of 2-pentyl-2-cyclopentenone (boiling point: 104° C./930 Pa; GC purity: 98.4%). In a 50 ml four-neck flask fitted with a thermometer, a reflux condenser and a stirrer was removed under refluxing followed by 4 hours of the reaction at 150° C The reaction mixture was washed with water the layers were separated from each other Further, the resulting organic layer was washed with saturated brine separated The organic layer was evaporated on a rotary evaporator under reduced pressure to recover toluene, whereby a crude product was obtained The product was distilled a Claisen distillation apparatus

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

Procedure: In a 100 ml four-neck flask fitted with a thermometer, a reflux condenser and a stirrer were placed 2-(1-hydroxypentyl)cyclopentanone (20 g) synthesized in Reference Example 1, iodine (0.01 g) and xylene (10 ml), and water was removed under refluxing, followed by 2 hours of the reaction at 170° C. The reaction mixture was washed with water and the layers were separated from each other. Further, the resulting organic layer was washed with saturated brine and separated. The organic layer was evaporated on a rotary evaporator under reduced pressure to recover xylene, whereby a crude product (19.8 g) was obtained. The product was distilled using a Claisen distillation apparatus to obtain 17.4 g of 2-pentyl-2-cyclopentenone (boiling point: 105° C./933 Pa; GC purity: 98.2%). In a 100 ml four-neck flask fitted with a thermometer, a reflux condenser and a stirrer was removed under refluxing followed by 2 hours of the reaction at 170° C The reaction mixture was washed with water the layers were separated from each other Further, the resulting organic layer was washed with saturated brine separated The organic layer was evaporated on a rotary evaporator under reduced pressure to recover xylene, whereby a crude product (19.8 g) was obtained The product was distilled a Claisen distillation apparatus

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

Procedure: In a 100 ml four-neck flask fitted with a thermometer, a reflux condenser and a stirrer were placed 2-(1-hydroxypentyl)cyclopentanone (20 g) synthesized in Reference Example 1, iodine (0.01 g) and xylene (10 ml), and water was removed under refluxing, followed by 2 hours of the reaction at 170° C. The reaction mixture was washed with water and the layers were separated from each other. Further, the resulting organic layer was washed with saturated brine and separated. The organic layer was evaporated on a rotary evaporator under reduced pressure to recover xylene, whereby a crude product (19.8 g) was obtained. The product was distilled using a Claisen distillation apparatus to obtain 17.4 g of 2-pentyl-2-cyclopentenone (boiling point: 105° C./933 Pa; GC purity: 98.2%). In a 100 ml four-neck flask fitted with a thermometer, a reflux condenser and a stirrer was removed under refluxing followed by 2 hours of the reaction at 170° C The reaction mixture was washed with water the layers were separated from each other Further, the resulting organic layer was washed with saturated brine separated The organic layer was evaporated on a rotary evaporator under reduced pressure to recover xylene, whereby a crude product (19.8 g) was obtained The product was distilled a Claisen distillation apparatus

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

Procedure: In a 300 ml four-neck flask fitted with a thermometer, a reflux condenser and a stirrer were placed 2-(1-hydroxypentyl)cyclopentanone (70 g) synthesized in Reference Example 1, oxalic acid (0.7 g) and toluene (140 ml), and the whole was refluxed to allow dehydration to proceed. The formed water was removed and the reaction was continued until water was not formed any more (about 2.5 hours). The reaction mixture was washed with water and the layers were separated from each other. The resulting organic layer was further washed with saturated brine and separated. The organic layer was evaporated on a rotary evaporator under reduced pressure to recover toluene and unreacted cyclopentanone, whereby a crude product (63 g) was obtained. The product was distilled using a Widmer distillation apparatus to obtain 52 g of 2-pentylidenecyclopentanone (boiling point: 92° C./533 Pa). In a 300 ml four-neck flask fitted with a thermometer, a reflux condenser and a stirrer the whole was refluxed The formed water was removed was not formed any more (about 2.5 hours) The reaction mixture was washed with water the layers were separated from each other The resulting organic layer was further washed with saturated brine separated The organic layer was evaporated on a rotary evaporator under reduced pressure to recover toluene and unreacted cyclopentanone, whereby a crude product (63 g) was obtained The product was distilled a Widmer distillation apparatus

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

Procedure: In a 300 ml four-neck flask fitted with a thermometer, a reflux condenser and a stirrer were placed 2-(1-hydroxypentyl)cyclopentanone (70 g) synthesized in Reference Example 1, oxalic acid (0.7 g) and toluene (140 ml), and the whole was refluxed to allow dehydration to proceed. The formed water was removed and the reaction was continued until water was not formed any more (about 2.5 hours). The reaction mixture was washed with water and the layers were separated from each other. The resulting organic layer was further washed with saturated brine and separated. The organic layer was evaporated on a rotary evaporator under reduced pressure to recover toluene and unreacted cyclopentanone, whereby a crude product (63 g) was obtained. The product was distilled using a Widmer distillation apparatus to obtain 52 g of 2-pentylidenecyclopentanone (boiling point: 92° C./533 Pa). In a 300 ml four-neck flask fitted with a thermometer, a reflux condenser and a stirrer the whole was refluxed The formed water was removed was not formed any more (about 2.5 hours) The reaction mixture was washed with water the layers were separated from each other The resulting organic layer was further washed with saturated brine separated The organic layer was evaporated on a rotary evaporator under reduced pressure to recover toluene and unreacted cyclopentanone, whereby a crude product (63 g) was obtained The product was distilled a Widmer distillation apparatus

Conditions: temp:2.51; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Into a 2-litter four-neck flask fitted with a thermometer, a reflux condenser and a stirrer were added sodium hydroxide (3.2 g) and water (300 ml). Then, a mixture of pentanal (86 g) and cyclopentanone (152 g) was added dropwise with stirring at 0-5° C. over a period of 2 hours. After the addition, the reaction mixture was stirred at room temperature for 1 hour to complete the reaction. Hexane (150 ml) was added to the reaction mixture and the layers were separated from each other. The resulting organic layer was washed with an aqueous solution (200 ml) of acetic acid (1 g) and then separated. The resulting organic layer was washed with saturated brine and separated. The organic layer was evaporated on a rotary evaporator under reduced pressure to recover hexane and unreacted cyclopentanone, whereby a crude product (173 g) was obtained. The product was distilled using a Claisen distillation apparatus to obtain 127 g of 2-(1-hydroxypentyl)cyclopentanone (boiling point: 115° C./933 Pa; GC purity: 95%). The remaining 5% was 2-pentylidenecyclopentanone which is a dehydration product. Into a 2-litter four-neck flask fitted with a thermometer, a reflux condenser and a stirrer was added dropwise After the addition the reaction mixture was stirred at room temperature for 1 hour the reaction the layers were separated from each other The resulting organic layer was washed with an aqueous solution (200 ml) of acetic acid (1 g) separated The resulting organic layer was washed with saturated brine separated The organic layer was evaporated on a rotary evaporator under reduced pressure to recover hexane and unreacted cyclopentanone, whereby a crude product (173 g) was obtained The product was distilled a Claisen distillation apparatus

Conditions: temp:130.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 42.6 g of 2-(1-hydroxypentyl)-cyclopentanone were dissolved in 161.9 g of n-butanol and heated to 130° C. Then, 24.5 g (0.24 mol) of a 35% hydrochloric acid were added dropwise thereto for 30 minutes at the same temperature. After the dropping addition was finished, the resultant mixture was stirred for 2 hours under heating at the same temperature. After the reaction was finished, the mixture was cooled to the room temperature and neutralized with an aqueous solution of sodium hydroxide. Then, the resultant organic layer was analyzed in the same manner as in Example 8. As the result, 22.9 g of 2-pentyl-2-cyclopentenone were obtained (yield: 60.0%). After the dropping addition under heating at the same temperature the mixture was cooled to the room temperature

Conditions: temp:130.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 42.6 g of 2-(1-hydroxypentyl)-cyclopentanone were dissolved in 161.9 g of n-butanol and heated to 130° C. Then, 24.5 g (0.24 mol) of a 35% hydrochloric acid were added dropwise thereto for 30 minutes at the same temperature. After the dropping addition was finished, the resultant mixture was stirred for 2 hours under heating at the same temperature. After the reaction was finished, the mixture was cooled to the room temperature and neutralized with an aqueous solution of sodium hydroxide. Then, the resultant organic layer was analyzed in the same manner as in Example 8. As the result, 22.9 g of 2-pentyl-2-cyclopentenone were obtained (yield: 60.0%). After the dropping addition under heating at the same temperature the mixture was cooled to the room temperature