2-alpha-hydroxyalkyl- and 2,7-di(alpha-hydroxyalkyl)-1,8-bis(dimethylamino)naphthalenes: stabilization of nonconventional in/out conformers of "proton sponges" via N...H-O intramolecular hydrogen bonding. A remarkable kind of tandem nitrogen inversion.
A regular set of 2-(alpha-hydroxymethyl)- and 2,7-di(alpha-hydroxymethyl)-1,8-bis(dimethylamino)naphthalenes has been prepared. Their X-ray, NMR, and IR studies have demonstrated that in tertiary mono-alcohols the orientation of free nitrogen electron pairs in crystals and solution corresponds to nonconventional in/out conformers stabilized by O-H...N intramolecular hydrogen bonding. For tertiary 2,7-dialcohols, the superimposed equilibrating in/out-out/in nitrogen invertomers are observed in solution. Unlike this, primary and secondary mono- and dialcohols commonly exist in the in/in form, which is typical for the parent proton sponge and the majority of its derivatives.
Pozharskii
Alexander F
AF
Department of Organic Chemistry, Southern Federal University, Zorge 7, 344090 Rostov-on-Don, Russian Federation. apozharskii@rsu.ru
Degtyarev
Alexander V
AV
Ryabtsova
Oksana V
OV
Ozeryanskii
Valery A
VA
Kletskii
Mikhail E
ME
Starikova
Zoya A
ZA
Sobczyk
Lucjan
L
Filarowski
Alexander
A