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 L-Serine,O-(triphenylmethyl)-
25840-83-9

L-Serine,O-(triphenylmethyl)- synthesis

3synthesis methods
-

Yield:25840-83-9 60.61%

Reaction Conditions:

Stage #1: L-serin;trityl chloride;mercury dichloride in acetonitrile at 40;
Stage #2: with triethylamine in acetonitrile at 20; for 1 h;Product distribution / selectivity;

Steps:

15

Example 15:H-Ser(Tr)-OH (O-trityl serine) by selective 0- tritylation of serine.; 0.2 g of serine (1.9 mmol) require about 0.5 h to dissolve in a solution of 1.06 g of trityl chloride (3.8 mmol) and 0.52 g of HgCl2 (1.9 mmol) in 15 mL of EPO acetonitrile, kept at 4O0C and under stirring. The slow addition of 0.27 ?iL of TEA (1.9 mmol) causes the precipitation of a heavy solid. After completing the addition of the base, the suspension is kept under stirring and at ambient temperature for another hour. To the dense mixture thus obtained is cautiously added an excess of sodium borohydride. It is allowed to react for 15 min, then 5 ml of NaOH IM are cautiously added, and subsequently 10 mL of water. Under agitation, the pH is brought to 3 with hydrochloric acid and filtration is applied, isolating a grey solid. The filtrate, after neutralisation with TEA, is concentrated under vacuum to about 15 mL, obtaining the precipitation of a white solid. By filtration, washing with water and drying a crude solid is obtained, which still needs to be washed with chloroform. The final solid weights 0.44 g (th. 0.66, 66.6%; m. p. 182 - 1840C; an.: C 75.80 (76.06), H 6.40 (6.09) , N 3.97 (4.03) .

References:

WO2007/9944,2007,A1 Location in patent:Page/Page column 30-31

L-Serine,O-(triphenylmethyl)- Related Search: