Processes for preparation of organic compounds
View Patent ↗The present invention provides a method for preparing an organic compound, which comprises a dehydration step of distilling off water from a polar organic solvent solution containing the organic compound and water to bring the concentration of water below a given level, wherein the dehydration step comprises distilling off water together with the polar organic solvent while adding a polar organic solvent to the solution, or comprises repeating several cycles of adding a polar organic solvent to the solution and then distilling off water together with the polar organic solvent. The present invention further provides the preparation of an organic compound, which enables efficient isolation of the target product in high isolated yield from a polar organic solvent solution containing the organic compound, water and, if necessary, a compound which produces, upon coming into contact with water or the like, a substance accelerating the decomposition of the organic compound.
1. A method for preparing a β-lactam compound, which comprises the following steps:
reacting a compound of Formula (2),
wherein A represents a condensed heterocyclic group having a β-lactam ring structure, and M represents a hydrogen atom or a metal atom, in a polar organic solvent, with a 4-halogenomethyldioxolenone compound of Formula (3),
wherein R 1 and R 2 each independently represent a hydrogen atom, an optionally substituted C 1 -C 6 alkyl group or an optionally substituted phenyl group, or R 1 and R 2 together form an optionally substituted C 3 -C 8 ring, and X represents a halogen atom, to result in a reaction solution containing a β-lactam compound in the polar organic solvent;
dehydrating a polar organic solvent solution obtained as the reaction solution or obtained by working up the reaction solution, to bring the concentration of water below a given level, wherein the dehydration step comprises distilling off water together with the polar organic solvent while adding a polar organic solvent to the solution, or comprises repeating two or more cycles of adding a polar organic solvent to the polar organic solvent solution and then distilling off water together with the polar organic solvent wherein the polar organic solvent further contains an iodine compound.
2. The method for preparing a β-lactam compound according to claim 1 , wherein the iodine compound is iodine or a metal iodide.
3. The method for preparing a β-lactam compound according to claim 1 , wherein the polar organic solvent solution is a solution in an ether solvent or a ketone solvent.
4. The method for preparing a β-lactam compound, which comprises the dehydration step according to claim 1 , wherein the dehydration step is followed by a crystallization step of distilling off the polar organic solvent from the resulting solution while supplementing the solution with a poor solvent for the organic compound so as to crystallize the organic compound.
5. The method for preparing a β-lactam compound according to claim 4 , wherein an alcohol solvent is used as the poor solvent.