Cyclopropenimine as a hydrogen bond acceptor-towards the strongest non-phosphorus superbases

被引：15

作者：

Baric, Danijela ^{[1
]}

Dragicevic, Ivan ^{[1
]}

Kovacevic, Borislav ^{[1
]}

机构：

[1] Rudjer Boskovic Inst, Quantum Organ Chem Grp, Div Organ Chem & Biochem, Zagreb 10000, Croatia

来源：

TETRAHEDRON | 2014年 / 70卷 / 45期

关键词：

Organic superbase; Hydrogen bonds; DFT calculations; Proton affinity; PKa; UNCHARGED AUXILIARY BASES; STRONG NONIONIC BASES; STRUCTURAL FEATURES; ORGANIC-MOLECULES; GUANIDINE BASES; BASICITY SCALE; GAS-PHASE; DESIGN; POLYAMINOPHOSPHAZENES; PROAZAPHOSPHATRANES;

D O I：

10.1016/j.tet.2014.09.068

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Utilizing dialkylamino cyclopropenimines as hydrogen bond acceptors in tri-substituted guanidines and cyclopropenimines, we computationally designed the most basic superbases possessing intramolecular hydrogen bonds (IHB-superbases) so far. The values of proton affinity in the gas phase range between 296.6 and 306 kcal mol(-1), with estimated pK(a) values in acetonitrile between 35.5 and 39.7. The obtained PAs of five new IHB-superbases surpass the basicity of the paradigmatic P4-tBu Schwesinger phosphazene, whereas pK(a) values come close to that of P4-tBu. None of the designed superbases contain phosphorus, which puts them among few most basic non-phosphorus superbases desiged so far. (C) 2014 Elsevier Ltd. All rights reserved.

引用

页码：8571 / 8576

页数：6

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