title: Naphthalene proton sponges as hydride donors: diverse appearances of the tert-amino-effect.
abstract: It has been shown that the 1-NMe(2) group in the 2-substituted 1,8-bis(dimethylamino)naphthalenes (proton sponges) can intramolecularly donate a hydride ion to an appropriate electron-accepting ortho-substituent such as diarylcarbenium ion, β,β'-dicyanovinyl or methyleneiminium group. This produces the 1-N(+)(Me)=CH(2) functionality and triggers a number of further transformations (tert-amino effect) including peri-cyclization, ortho-cyclization or hydrolytic demethylation. In each particular case, the course of the reaction is determined by the nature of the ortho-substituent and the most potent nucleophile presenting in the reaction mixture. For 2,7-disubstituted 1,8-bis(dimethylamino)naphthalenes, two types of tandem tert-amino effect with the involvement of both peri-NMe(2) groups have been registered. The conclusion was made that proton sponges are generally more active in the tert-amino reactions than the corresponding monodimethylaminoarenes. This is ascribed both to higher electron donor ability of proton sponges and markedly shortened distance between electrophilic C(α)-atom in the ortho-substituent and hydrogen atoms of the nearest NMe(2) group. Most conversions observed proceed in good to high yields and are useful for the preparation of derivatives of benzo[h]quinoline, quino[7,8:7',8']quinoline, 2,3-dihydroperimidine, N,N,N'-trimethyl-1,8-diaminonaphthalene and proton sponge itself.
authors.affiliation: Department of Organic Chemistry, Southern Federal University, Zorge 7, 344090 Rostov-on-Don, Russian Federation. apozharskii@sfedu.ru
authors.forename: Alexander F
authors.initials: AF
authors.lastname: Pozharskii
authors.forename: Maria A
authors.initials: MA
authors.lastname: Povalyakhina
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Degtyarev
authors.forename: Oxana V
authors.initials: OV
authors.lastname: Ryabtsova
authors.forename: Valery A
authors.initials: VA
authors.lastname: Ozeryanskii
authors.forename: Olga V
authors.initials: OV
authors.lastname: Dyablo
authors.forename: Anna V
authors.initials: AV
authors.lastname: Tkachuk
authors.forename: Olga N
authors.initials: ON
authors.lastname: Kazheva
authors.forename: Anatolii N
authors.initials: AN
authors.lastname: Chekhlov
authors.forename: Oleg A
authors.initials: OA
authors.lastname: Dyachenko