Hydrogen bonding. VI. Dramatic difference between proton transfer and hydrogen bonding

Basicity. Comparison of hydrogen bonding and proton transfer to some Lewis bases

“…AH¡ measurements are readily obtained for the protonation of most bases in this single medium in which the protonation process is complete and well defined, as is shown by freezing point depressions, electrical conductivities, nmr observations, and ultraviolet spectroscopy.27•28 •81 Several years ago we noted that a surprisingly good linear correlation is found between AH, and pK& for many compounds including a variety of weak bases whose pAVs have been determined by acidity function methods. In view of the errors in many previous p^fB estimates17 and the availability of a number of new nitrobenzene, (3) 2,4,6-trinitroaniline, (4) acetonitrile, (5) 2-bromo-4,6-dinitroaniline, (6) 2,6-dinitroaniline, (7) diethyl sulfide, (8) 2,4-dinitroaniline, (9) diethyl ether, (10) 2,6-dichloro-4-nitroaniline, (11) 1,4-dioxane, (12) diphenylcyclopropenone, (13) triphenylphosphine oxide, (14) tetrahydrofuran, (15) 2,5-dichloro-4-nitroaniline, (16) Ar,,V-dimethylbenzamide, (17) 4-chloro-2-nitroaniline, (18) 2-nitroaniline, (19) A/.V-dimethylacetamide, (20) A7-methylformamide, (21) AyV-dimethylformamide, (22) dimethyl sulfoxide, (23) 2-chloropyridine, (24) pyridine Ar-oxide, (25) 2-bromopyridine, (26) 2,4,6-tribromoaniline, (27) 4-nitroaniline, (28) 2,4-dichloroaniline, (29) 3-nitroaniline, (30) 2-iodoaniline, (31) 2-chloroaniline, (32) triphenylphosphine, (33) 3-bromopyridine, (34) 2-fluoroaniline, (35) 3-chloroaniline, (36) 4-iodoaniline, (37) 4-bromoaniline, (38) 4-chloroaniline, (39) 2-methylaniline, (40) aniline, (41) 4-fluoroaniline, (42) quinoline, (43) V,A'-dimethylaniline, (44) 4-methylaniline, (45) pyridine, (46) 4-methylpyridine, (47) 2,6-dimethylpyridine, (48) 2,4,6-trimethylpyridine, (49) tri-zi-butylamine, (50) triethylamine, (51) quinolidine, (52) diethylamine, (53) di-zz-butylamine, (54) phenyl methyl sulfoxide, (55) 2,6-dimethyl-7-pyrone, (56) A'-methyl-2-pyrrolidone.…”

“…Plot of AH¡ vs. AHi for amides, phosphoroxy compounds, pyridines, sulfides, and sulfoxides. Data points in the figure refer to the following compounds: (1) .V,.V-dimethyltrifluoroacetamide, (2) .V-methylformamide, (3) ,VyV-dimethylchloroacetamide, (4) Ar,A7-dimethylbenzamide, (5) A.V-dimethylformamide, (6) Af-methyl-2-pyrrolidone, (7)7V,A'-dimethylacetamide, (8) 1,1,3,3-tetramethylurea, (9) phosphoroxychloride, (10) dichlorophenylphosphine oxide, (11) diethyl chlorophosphate, (12) trimethyl phosphate, (13) triethyl phosphate, (14) triphenylphosphine oxide, (15) diethyl ethylphosphonate, (16) trimethylphosphine oxide, (17) 3,5-dichloropyridine, (18) 2-bromopyridine, ( 19) 2-chloropyridine, (20) 3-bromopyridine, (21) quinoline, (22) pyridine, (23) 4-methylpyridine, (24) 2,6-dimethylpyridme, (25) 2,4,6-trimethylpyridine, (26) diphenyl sulfide, (27) phenyl methyl sulfide, (28) chloromethyl methyl sulfide, (29) di-zz-butyl sulfide, (30) diethyl sulfide, (31) tetrahydrothiophene, (32) dimethyl sulfoxide, (36) di-zt-butyl sulfoxide, (37) tetramethylene sulfoxide; (O) amides, ( ) phosphoroxy compounds, ( ) pyridines, (•) sulfides, (B) sulfoxides.…”

Molecular recognition at the gas–solid interface: a powerful tool for chemical sensing

“…The focus is on phosphonate cavitands because of their better H-bonding acceptor ability with respect to the corresponding phosphates. 22 The presence of four long alkyl chains at the lower rim is needed to obtain highly permeable amorphous layers, that allow easier access of the analytes to the bulk of the layer (see Fig. 4).…”

Nature and Estimation of Functional Groups on Solid Surfaces

“…the energy of specific interaction, and is determined by the acceptor strength of the H-bond acceptor and by the donor strength of the OH group as well. Although the possible differences between proton transfer (acidity) and H-bonding had been pointed out [164], a number of attempts have been undertaken to …”