Combined use of three forms of chiroptical spectroscopies in the study of the absolute configuration and conformational properties of 3-phenylcyclopentanone, 3-phenylcyclohexanone, and 3-phenylcycloheptanone

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• 作者：Patrizia Scafato ; Francesca Caprioli ; Laura Pisani ; Daniele Padula ; Fabrizio Santoro ; Giuseppe Mazzeo ; Sergio Abbate ; France Lebon ; Giovanna Longhi
• 关键词：ORD ; ECD ; VCD ; Vibronic features ; Absolute configuration ; Conformations ; Phenyl hindered rotation
• 刊名：Tetrahedron
• 出版年：16 December, 2013
• 年：2013
• 卷：69
• 期：50
• 页码：10752-10762
• 全文大小：2845 K

文摘

Three forms of chiroptical spectroscopies, electronic circular dichroism (ECD), vibrational circular dichroism (VCD), and optical rotatory dispersion (ORD) have been employed to study the configuration and聽conformational properties of the three molecules: (S)-3-phenylcyclopentanone, (S)-3-phenylcyclohexanone, and (S)-3-phenylcycloheptanone (including (S)-3-phenylcyclopentanone-2,2,5,5-d₄ and (S)-3-phenylcyclohexanone-2,2,6,6-d₄). ECD and VCD spectra in the mid-IR for the three molecular systems are marginally dependent on fine conformational details, as interpreted in terms of standard DFT computational methods, with common spectroscopic features to the three systems clearly identified. Accounting for vibronic coupling mechanisms reproduces the structuring of ECD n鈫捪€^{鈭?/sup> band. The ORD curves are quite similar for the three types of molecules, but their interpretation highlights a crucial role played by conformations of the cycloalkanone ring in the case of (S)-3-phenylcycloheptanone. The same conclusions are reached by considering the VCD spectra in the CH-stretching region.}