Synthesis and fungicidal activity of (2-chloropyridin-5-yl) methyl carbamates

Eleven novel(2-chloropyridin-5-yl)methyl carbamates were synthesized by Pd-Fe/TiO2 catalyzed carbonylation of aromatic nitro-compounds and(2-chloropyridin-5-yl)methanol with carbon monoxide. Their structures were confirmed by 1H NMR and MS. Preliminary fungicidal activity tests indicated that some of the target compounds exhibited certain degree of inhibiting effect against four tested strains at the concentration of 50 mg/L. The inhibition rate against Gibberella zeae was over 77.3% for compound 3f (2-chloropyridin-5-yl) methyl(4-methoxyphenyl)carbamate, 3h 2-chloropyridin-5-yl)methyl(2,4-dichlorophenyl)carbamate and 3j (2-chloropyridin-5-yl) methyl(3,4-dichlorophenyl) carbamate. Compound 3f showed 82.5% of inhibition rate against Physalospora piricola, that was almost equal to carbendazim. All compounds showed better fungicidal activities against Botrytis cinerea than carbendazim.