天堂网亚洲,天天操天天搞,91视频高清,菠萝蜜视频在线观看入口,美女视频性感美女视频,95丝袜美女视频国产,超高清美女视频图片

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 methyl 5-bromo-2-methyl-benzoate
79669-50-4

methyl 5-bromo-2-methyl-benzoate synthesis

13synthesis methods
-

Yield:79669-50-4 99%

Reaction Conditions:

Stage #1:methanol;5-bromo-2-methylbenzoic acid with diazomethyl-trimethyl-silane in hexane at 20; for 1.16667 h;
Stage #2: with acetic acid in hexane for 0.75 h;

Steps:

5
Place 5-bromo-2-methyl-benzoic acid (1.0 g, 4.7 mmol) in a 200 mL flask under an N2 atmosphere and add methanol via syringe. Add a 2M solution of diazomethyl- trimethyl-silane in hexane (3.5 mL, 23.0 mmol) drop wise over 10 minutes and stir for 1 hour at room temperature. Add glacial acetic acid (16 mL) and stir for 45 minutes. Dilute with ethyl acetate (100 mL) and wash with 1M aqueous sodium hydroxide solution (30 mL), saturated aqueous sodium bicarbonate solution (30 mL) and brine (30 mL). Dry the organic layer (Na2SO4), filter and concentrate in vacuo to obtain 1.01 g of 5-bromo-2- methyl-benzoic acid methyl ester (99 %). Place 5-bromo-2-methyl-benzoic acid methyl ester (1.04 g, 4.5 mmol) in a 50 mL flask under a N2 atmosphere and add carbon tetrachloride (15 mL). Add N-bromo- succinamide (1.49 g, 8.3 mmol) and 2,2'-azobisisobutyronitrile (40 mg, 0.2 mmol) and fit flask with a condenser and reflux for 4 hours. Cool to room temperature and filter. Concentrate the filtrate and pre-adsorb the crude product onto silica gel. Chromatograph the residue on a Si02 column eluting with dichloromethane in hexane (0 to 50%) to obtain 977 mg of 5-bromo-2-bromomethyl-benzoic acid methyl ester (70%). Using 5-bromo-2-bromomethyl-benzoic acid methyl ester (0. 984 g, 3.20 mmol) and the procedure described in the I st paragraph for the alternative procedure for 5- (4,4, 5, 5-tetramethyl- [1, 3,2] dioxaborolan-2-yl) -2, 3-dihydro-isoindol-1-one, prepare 509 mg of the title compound (75 %).

References:

ELI LILLY AND COMPANY WO2005/73205, 2005, A1 Location in patent:Page/Page column 27-28

FullText

methyl 5-bromo-2-methyl-benzoate Related Search: