成人免费xx,国产又黄又湿又刺激不卡网站,成人性视频app菠萝网站,色天天天天

Welcome to chemicalbook!
Chinese English Japanese Germany Korea
400-158-6606
Try our best to find the right business for you.
Do not miss inquiry messages Please log in to view all inquiry messages.

Welcome back!

ChemicalBook CAS DataBase List (S)-(+)-5-(Hydroxymethyl)-2-pyrrolidinone p-toluenesulfonate
51693-17-5

(S)-(+)-5-(Hydroxymethyl)-2-pyrrolidinone p-toluenesulfonate synthesis

8synthesis methods
-

Yield:-

Reaction Conditions:

with sodium borohydrid in dichloromethane;water;acetone

Steps:

9 (S)-5-Tosyloxymethyl-2-pyrrolidinone
EXAMPLE 9 (S)-5-Tosyloxymethyl-2-pyrrolidinone Ethyl (L)-pyroglutamate (15.7 g), dissolved in water (50 ml) is added slowly at 0° C. to a solution of sodium borohydride (2.2 g) in water (50 ml). The mixture is allowed to warm up over a one-hour period after which it is stirred at room temperature for 20 minutes. Acetone (5 ml) is added and the stirring is continued for 30 minutes. Solvent is evaporated to give a dry residue which is dissolved in water (100 ml). The solution is then concentrated to a volume of 40 ml. To the concentrated solution are added: caustic soda (5 g), tosyl chloride (18.10 g) in dichloromethane (100 ml), and tetra-n-butyl ammonium hydrogen sulfate (1.03 g). The resulting mixture is stirred vigorously for 42 hours at room temperature. The organic layer is separated, and the aqueous layer is extracted with dichloromethane (50 ml). The organic layers are combined and dried. Evaporation of solvent gives a residue which is recrystallized from toluene (150 ml) to give 13.6 g of pure (S)-5-tosyloxymethyl-2-pyrrolidinone, [α]D =+7.80+-0.04 (c=2.64, EtOH).

References:

Merrell Dow Pharmaceuticals Inc. US4621145, 1986, A

(S)-(+)-5-(Hydroxymethyl)-2-pyrrolidinone p-toluenesulfonate Related Search: