2-heptylidenecyclopentan-1-one

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

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-heptylidenecyclopentanone (20 g) synthesized in Reference Example 6, bromine (0.05 g) and tetrachloroethylene (10 ml), followed by 4 hours of the reaction under refluxing. 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 tetrachloroethylene, whereby a crude product (19 g) was obtained. The product was distilled using a Claisen distillation apparatus to obtain 16.8 g of 2-heptyl-2-cyclopentenone (boiling point: 111° C./900 Pa; GC purity: 97.3%). In a 100 ml four-neck flask fitted with a thermometer, a reflux condenser and a stirrer followed by 4 hours of the reaction under refluxing 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 tetrachloroethylene, whereby a crude product (19 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-hydroxyheptyl)cyclopentanone (70 g) synthesized in Reference Example 3, 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. 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 and unreacted cyclopentanone, whereby a crude product (63 g) was obtained. The product was distilled using a Claisen distillation apparatus to obtain 55 g of 2-heptylidenecyclopentanone (boiling point: 56° C./400 Pa; GC purity: 98.5%). 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 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 and unreacted cyclopentanone, whereby a crude product (63 g) was obtained The product was distilled a Claisen distillation apparatus