反应详情

To a solution of dichloro(p-cymene)ruthenium (II) dimer (250 mg) and 2,6-bis[(4S)isopropyl-2-oxazolin-2-yl]pyridine (240 mg) in dichloromethane (150 ml) was added 1-methoxy-4-vinylbenzene (25 g). To this solution was added ethyl diazoacetate (5.0 g) in dichloromethane (20 ml) over 6 hours. The solution was maintained at room temperature for 18 hours then diluted with i-hexane (200 ml) and passed through a plug of silica (50 g) washing with i-hexane/dichloromethane (1:1, 250 ml). The filtrate was concentrated and the residue taken into methanol (100 ml). Lithium hydroxide (4.0 g) in water (10 ml) was added and the mixture heated at reflux for 4 hours. The resulting solution was concentrated to give a solid which was washed with 1:1 ether/i-hexane (100 ml). The solid was then triturated with 2N HCl and the white precipitate collected to give the subtitle compound (5.1 g).

1. washwashing with i-hexane/dichloromethane (1:1, 250 ml)
2. concentrationThe filtrate was concentrated
3. additionLithium hydroxide (4.0 g) in water (10 ml) was added
4. temperaturethe mixture heated
5. temperatureat reflux for 4 hours
6. concentrationThe resulting solution was concentrated
7. customto give a solid which
8. washwas washed with 1:1 ether/i-hexane (100 ml)
9. customThe solid was then triturated with 2N HCl
10. customthe white precipitate collected