Accurate theoretical method for homolytic cleavage of C–Sn bond: A benchmark approach

Stille coupling is a well-known cross coupling reaction, where the rate determination step is the dissociation of carbon stannous (C–Sn) bond. The organotin compounds are also used as precursors in the manufacturing of tin oxide films, solar cells, gas sensors, flat panel display technology and low emission glass materials, etc. The reactivity of organotin compounds has direct relationship with the homolytic cleavage of C–Sn bond. Therefore, accurate determination of C–Sn bond has direct relevance in understanding many phenomena. The current benchmark study is aimed at finding out the accurate theoretical method for the homolytic cleavage (bond dissociation energy) of C–Sn bond. In this regard, nineteen DFs from eight different classes of DFT with two effective core potential basis sets (LANL2DZ and SDD) and two Karlsruhe basis sets (def2-SVP and def2-TZVP) are selected for the BDE calculation of C–Sn bond. Ten structurally diverse organotin compounds with experimentally known BDE of C–Sn bond are selected from the literature. The statistical [root mean square deviation (RMSD), standard deviation (SD), Pearson's correlation (R) and mean absolute error (MAE)] results are obtained by the comparison of theoretical data with the experimental BDE values of C–Sn bond of selected organotin compounds. Among all DFT classes, GGA-D class is a batter class and BLYP-D3 functional of this class is selected as the best functional for homolytic bond dissociation energy (BDE) calculation of C–Sn bond. This functional with SDD basis set shows remarkable performance in reproducing the BDE of C–Sn bond with more accuracy. The SD, RMSD, R and MAE are 4.11 kcal mol⁻¹ is 3.9 kcal mol⁻¹ is 0.963 and −0.01 kcal mol⁻¹, respectively.