Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 33993-24-7, name is Cyclopropanecarboxylic anhydride, A new synthetic method of this compound is introduced below., Safety of Cyclopropanecarboxylic anhydride
Example 9 (diastereomeric mixture)To a solution of example 9a (0.055 g, 0.12 mmol) in dry ACN (2 mL), dicyclopropyl anhydride (0.075 g, 90% content, 0.44 mmol, prepared as described in J. Org. Chem., 67, 5226-5231; 2002) and dry TEA (0.088 mL, 0.62 mmol) are added and the mixture heated under microwaves irradation (100C) for 50 min and then heated at 150C for additional 30 min. Solvents evaporated, crude purified by flash cromatography (cycloheane/EtOAc from 50:50 to 20:80) to obtain the title compound (0.033 g, 54%).HPLC-MS (Method 6): Rt = 10.80 minMS (ESI pos): m/z = 486 (M+H)+ The diastereoisomers of the title compound are separated by HPLC using a chiral stationary phase.Method for separation:HPLC apparatus type: Agilent 1100; column: Daicel chiralpack AS-H, 5.0 muiotaeta, 250 mm x 20 mm; method: eluent hexane/EtOH 70:30; flow rate: 15 mL/min, Temperature: 25C; UV Detection: 230 nm Example of separation by chiral HPLC:Sumitted to separation: 200 mg of Example 9Obtained: 84 mg of Diastereoisomer 1 (Exp. 10) and 78 mg of Diastereoisomer 2 (Exp.11)Example Chiral HPLC HPLC-MS (Method 5): MS (APCI pos):Rt [min] Rt [min] m/z
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Patent; BOEHRINGER INGELHEIM INTERNATIONAL GMBH; GIOVANNINI, Riccardo; BERTANI, Barbara; FERRARA, Marco; LINGARD, Iain; MAZZAFERRO, Rocco; ROSENBROCK, Holger; WO2013/17657; (2013); A1;,
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