Author/Authors :
Jaspreet S. Dhau، نويسنده , , Amritpal Singh، نويسنده , , Yoganjaneyulu Kasetti، نويسنده , , Sonam Bhatia، نويسنده , , Parsad V. Bharatam، نويسنده , , Paula Brand?o، نويسنده , , V?tor Félix، نويسنده , , Kamal N. Singh، نويسنده ,
Abstract :
The BF3-directed lithiation of 3-chloro- and 3-bromopyridine (1a and 1b, respectively) has been investigated. The reactions of 3-chloro- or 3-bromopyridine–BF3 adduct with LDA (1.3/1.1 equiv) followed by quenching with benzaldehyde or iodine exclusively gave the C-2 substituted products. However, when 2.2 equiv of LDA and dimethyl disulfide was used, a C-6 substituted product was obtained. Dilithiation of 1a and 1b has been studied with and without the involvement of BF3 complexation. The role of Li⋯F(BF3) interactions has been investigated by experimental and DFT calculations.
Keywords :
3-Chloropyridine , 3-Bromopyridine , lithiation , Density functional calculation
