peri-Interactions in naphthalenes, 13 [1] 8-Dimethylamino-naphth-1-yl carbinols as model systems for potential N/Si/P interactio

In (8-dimethylamino-naphth-1-yl) (‘DAN’) carbinols DAN–C(OH)R1R2, the N atom can approach the HO group unto N/H-O hydrogen bond distance only when the steric conditions are favourable. The energy gain of such N/H–O interactions is insufficient to force R1 and R2 into otherwise unfavourable conformations. The geometry of the naphthalene may cause N, O and C atoms to reside in positions similar to those typical for hydrogen bonds though no N/H–O and N/H–C hydrogen bonds may actually be involved. By analogy, it seems unlikely that in peri-donor/acceptor substituted naphthalenes D–C10H6–A dative interactions (D/A) of similar or less energy as such N/H-O interactions can interfere with the geometry conserving forces of naphthalene and the steric effects of the peri substituents. q 2005 Elsevier B.V. All rights reserved