Protonated naphthalene proton sponges

The Potential Energy Shape for the Proton Motion in Protonated Naphthalene Proton Sponges (DMAN-s) and its Manifestations... 

Abstract The problem of the low-barrier hydrogen bond in protonated naphthalene proton sponges is reviewed. Experimental data related to the infra-red and NMR spectra are presented, and the isotope effects are discussed. An unusual potential for the proton motion that leads to a reverse anharmonicity was shown The potential energy curve becomes much steeper than in the case of the harmonic potential. The isotopic ratio, i.e., vH/VD (v-stretching vibration frequency), reaches values above 2. The MP2 calculations reproduce the potential energy curve and the vibrational H/D levels quite well. A critical review of contemporary theoretical approaches to the barrier height for the proton transfer in the simplest homoconjugated ions is also presented. 

PhCH20CH2Cl, Nal, proton sponge [l,8-bis(dimethylamino)naphthalene], 84% yield. BOMBr can also be used. ... 

Similar statements for IP(tt4) can be made for the two diaminonaphthalenes (15,16). Peri-substituted naphthalenes are examples of molecules with strong intramolecular crowding which can result in unique physicochemical properties. 1,8-Bis(dimethylamino)naphthalene (19) ( proton sponge 88,89) has been found to have an... 

Scheme 9.27 Decarboxylative allylic amidation. Proton sponge = 1,8-Bis-(dimethylamino)-naphthalene.

Some consideration was given to appropriate bases for this oxidation system. Pyridine and sodium bicarbonate had been shown to be useful earlier and were included. Additional bases considered were a proton sponge (1,8-Bis(dimethylamino)naphthalene) and, as stated above, pyridine N-oxide. Because of the low solubilities in CXL systems of NaHCOs and the proton-sponge, pyridine was selected for these exploratory studies. 

Pyrrolidines piperidines.D Suitably unsaturated a-iodo (or a-bromo) esters cyclize to pyrrolidines or piperidines in the presence of this Pd(0) catalyst and 1,8-bis(dimethylamino)naphthalene (proton sponge). 

The acylate anion from Mn(CO)3(j/-C5H5) and LiMe reacts similarly reaction with l,8-bis(dimethylamino)naphthalene (proton sponge) affords the vinylidene, although in this reaction, it is the binuclear complex which is isolated as the final product (38) ... 

A.F. Pozharskii, Naphthalene proton sponges (naftalinovye protonnye gubki). Usp. Khim. 67,... 

A.V. Degtyarev et al., 2,7-Disubstituted proton sponges as borderline systems for investigating barrier-free intramolecular hydrogen bonds. Protonated 2,7-bis(trimethylsilyl)-and 2,7-di (hydroxymethyl)-l,8-bis(dimethylamino)naphthalenes. Tetrahedron 64, 6209-6224 (2008)... 

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