Synthesis of Fused Pyran and Tetracyclic Pyran Rings  by Intramolecular Palladium-catalyzed β-H Elimination and  C–H  Bond Functionalization

Rathin Jana,1*Email

Mitali Dewan1 

Gourisankar Roymahapatra2

1Departnt of chemistry, Shahid Matangini Hazra Govt. college for women, nimtouri West bengal, India

2School of Applied Science and Humanities, Haldia Institute of Technology, haldia 721657, India

Abstract

Pyrans constitute an important class of 6-member heterocycles with one oxygen atom. Together with its benzo derivatives, pyrans can formulate a prevalent verity of natural and synthetic products with industrial applications. This is an important core molecule having versatile use with its derivatives in pharmaceuticals, dye industry, catalysis, agrochemicals any many more. Several methods for the preparation of pyran derivatives have been reported earlier. This article reports the development of an efficient method for the construction of a fused pyran ring by intramolecular Heck reaction followed by β-H elimination from O-allylated ether. A tetracyclic pyran ring has also been synthesized by intramolecular Heck reaction followed by C–H bond activation from O-methallylated ether.

Synthesis of Fused Pyran and Tetracyclic Pyran Rings  by Intramolecular Palladium-catalyzed β-H Elimination and  C–H  Bond Functionalization