681832-05-3Relevant academic research and scientific papers
Regioselectivities in deprotonation of 2-(4-chloro-2-pyridyl)benzoic acid and corresponding ester and amide
Rebstock, Anne-Sophie,Mongin, Florence,Trécourt, Fran?ois,Quéguiner, Guy
, p. 2181 - 2186 (2007/10/03)
Upon treatment of ethyl 2-(4-chloro-2-pyridyl)benzoic acid, 2-(4-chloro-2-pyridyl)benzoate, and N,N-diisopropyl-2-(4-chloro-2-pyridyl) benzamide with LTMP at -75°C in THF, the lithio derivatives at C5′ are generated regiospecifically, as demonstrated by subsequent quenching with electrophiles. The lithio derivative at C3′ is only evidenced from the benzamide at higher temperature (-50°C), when treated with LTMP in THF; it instantly cyclizes to 1-chloro-4-azafluorenone. The latter is converted to onychine, an alkaloid endowed with anticandidal activity.
