Silabenzenoids Containing Heteroatoms

FIGURE 7. MP2/6-31G optimized geometries of 41-44. Drawn from data in References 68 and 69 

The relative stability of the three silapyridines 42-44 follows the order (kcalmol-1) 42 (0.0, most stable) 44 (11.0) 43 (37.8), but no explanation was given for this stability order68. The thermodynamic stability of v-1,3,5-trisilatriazinc, 41, and of the silapyridines 42-44 relative to their isomeric silylenes is discussed in Section V.B.I. 

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