Amine superbases stabilized by extended hydrogen bond networks

摘要

Extended hydrogen-bonding networks as a mechanism for creating superbases is explored through six different amine scaffolds: linear acenes, cyclohexane, decalin, triptycene, adamantane, and [2.2]paracyclophane. The gas-phase proton affinities of 21 different potential superbases were computed at the ωB97X-D/6-311+G(2d,p) level. This method was benchmarked against the experimental proton affinities of 44 nitrogen bases. Extended hydrogen-bonding networks, including second- and third-layer hydrogen bonding, led to bases with proton affinities 20 kcal mol-1 greater than that of bis(dimethylamino)naphthalene. The strongest bases are the decalin base 25 and the adamantane base 31.