Pyridine → 1,1-Dichloroethane

Participants

Reaction Steps

In yet another process of the invention for the preparation of the compounds of Formula I, compound 5 of Scheme 2 is reacted with a sulphonyl halide such as methanesulfonyl chloride, toluenesulfonyl chloride, benzylsufonyl chloride and the like in an aprotic solvent such as pyridine, dichloromethane, dichloroethane, THF, DMF and the like optionally in the presence of a base such as triethyl amine, diisopropyl ethyl amine and the like at −78° C. to room temperature to provide the 4′-OSO2R′ intermediate which further is treated with NaI, KI, tetrabutyl ammonium iodide and the like in an aprotic solvents such as acetone, butanone, DMF, dioxane, and the like at from room temperature to 100° C. to provide the 4′-iodo intermediate, compound 8 (Scheme 4). The iodo functionality of compound 8 is removed by various reduction methods such as using tributyl tin hydride in the presence of AIBN in an organic solvent such as benzene, toluene, and the like or hydrogenolysis using Raney nickel in the presence of hydrogen in an organic solvent such as methanol, ethanol, ethyl acetate and the like to provide 4′-deoxy leucomycin derivatives, compound 9. Compound 9 can be converted to compound 10 via hydrolysis and methanolysis to deprotect the protecting groups as described earlier.

Provenance & Evidence