Analyzing the synthesis route of 108-55-4

As the paragraph descriping shows that 108-55-4 is playing an increasingly important role.

With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.108-55-4,Dihydro-2H-pyran-2,6(3H)-dione,as a common compound, the synthetic route is as follows.

To a stirred suspension of aluminum chloride (205.85g, 1. 54MOL) in dichloromethane(500ML) was added a solution of glutaric anhydride (80g, 0. 7MOL) indichloromethane (125ML) at 0C. The reaction mass was stirred for30minutes and fluorobenzene (67.36g, 0. 7MOL) was added to the reactionmass slowly. The reaction was monitored for completion by TLC and thenpoured into ice cold water (2000ML) under stirring and the separatedsolids were collected by filtration. The solids were dissolved in 3%aqueous sodium hydroxide solution (1100ML) and washed withdichloromethane (300ML). The aqueous layer was acidified to give aprecipitate. The solids were filtered and washed with water andvacuum-dried to yield the title product (125g, yield: 85%). LHNMR(CDC13) 8 : 8.027-7. 98 (M, 2H), 7.17-7. 11 (M, 2H), 3.067 (t, 2H), 2.52(t, 2H), 2.14-2. 04 (M, 2H).

As the paragraph descriping shows that 108-55-4 is playing an increasingly important role.

Reference£º
Patent; RANBAXY LABORATORIES LIMITED; WO2004/99132; (2004); A2;,
Tetrahydropyran – Wikipedia
Tetrahydropyran – an overview | ScienceDirect Topics