Dip. di Scienze e Tecnologie Chimiche, Università di Roma Tor Vergata, via della Ricerca Scientifica, 00133 Rome, Italy.
Phys Chem Chem Phys. 2011 Jan 21;13(3):818-24. doi: 10.1039/c0cp01401j. Epub 2010 Dec 6.
Diastereomeric adducts between (S)-1-(4-fluorophenyl)-ethanol and R and S 2-butanol, formed by supersonic expansion, have been investigated by means of a combination of mass selected resonant two-photon ionization-spectroscopy and infrared depletion spectroscopy. Chiral recognition is evidenced by the specific spectroscopic signatures of the S(1)← S(0) electronic transition as well as different frequencies and intensities of the OH stretch vibrational mode in the ground state. D-DFT calculations have been performed to assist in the analysis of the spectra and the determination of the structures. The homochiral and heterochiral complexes show slight structural differences, in particular in the interaction of the alkyl groups of 2-butanol with the aromatic ring. The experimental results show that the homochiral [FE(S)·B(S)] complex is more stable than the heterochiral [FE(S)·B(R)] diastereomer in both the ground and excited states. The binding energy difference has been evaluated to be greater than 0.60 kcal mol(-1).
通过超音速膨胀形成的（S）-1-（4-氟苯基）-乙醇和 R 和 S 2-丁醇的非对映异构体加合物，已通过质量选择共振双光子电离光谱和红外耗散光谱的组合进行了研究。手性识别是通过 S(1)←S(0)电子跃迁的特定光谱特征以及在基态中 OH 伸缩振动模式的不同频率和强度来证明的。进行了 D-DFT 计算以协助分析光谱和确定结构。同手性和异手性配合物显示出轻微的结构差异，特别是在 2-丁醇的烷基与芳环的相互作用方面。实验结果表明，在基态和激发态下，同手性[FE(S)·B(S)]配合物比异手性[FE(S)·B(R)]非对映异构体更稳定。结合能差被评估为大于 0.60 kcal mol(-1)。
