The methyl group as a source of structural diversity in heterocyclic chemistry: side chain functionalization of picolines and related heterocycles.
The reaction of 2-picoline at the methyl group with NDA and KDA followed by dimethyldisulfide trapping furnished, respectively, dithioacetals and trithioortho esters with high selectivity. The method was successfully applied to other methyl-substituted pyridines, quinolines, and pyrazines. Dithioketals were prepared by a one-pot procedure involving the reaction of metalated 2-picoline with 2 equiv of dimethyldisulfide followed by in situ trapping with a second electrophile. All of the generated thio-substituted compounds were efficiently transformed in presence of mercury salts or under oxidizing conditions to other functional groups comprising aldehydes, ketones, ketals, thiol esters, orthoesters, and esters.
Mamane
Victor
V
Laboratoire SRSMC, Equipe de Synthèse Organométallique et Réactivité, UMR CNRS-UHP 7565, Faculté des Sciences, Nancy-Université, BP 239, 54506 Vandoeuvre-Lès-Nancy, France. victor.mamane@sor.uhp-nancy.fr
Aubert
Emmanuel
E
Fort
Yves
Y
D000080:Acetals / Q000737:chemistry; D004952:Esters / Q000737:chemistry; D008628:Mercury / Q000737:chemistry; D008745:Methylation; D010847:Picolines / Q000737:chemistry*; D011719:Pyrazines / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D011804:Quinolines / Q000737:chemistry*
D000080:Acetals; D004952:Esters; D010847:Picolines; D011719:Pyrazines; D011725:Pyridines; D011804:Quinolines; D008628:Mercury