Intramolecular hydrogen bonding in conformationally semi-rigid α-acylmethane derivatives: a theoretical NMR study.

Antonio J Mota,Sébastien Lemouzy,Nuno Maulide,Martina Drescher,Jürgen Neuhold,Leticia González

doi:10.1039/c7ob01834g

Antonio J Mota, Sébastien Lemouzy + Show 4 more

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https://doi.org/10.1039/c7ob01834g

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Abstract

Conformational mobility is a core property of organic compounds, and conformational analysis has become a pervasive tool for synthetic design. In this work, we present experimental and computational (employing Density Functional Theory) evidence for unusual intramolecular hydrogen bonding interactions in a series of α-acylmethane derivatives, as well as a discussion of the consequences thereof for their NMR spectroscopic properties.

Highlights

Conformational flexibility is an intrinsic trait of most organic compounds.[1]
In order to eliminate any possible effect of the sulfur residue on the aromatic ring, we compared the known compound 1-Dec (R = Decyl) with its desulfurated analogue 2-Dec
We resorted to high-level density functional theory (DFT) calculations since it is well-known that general purpose, theoretical 1H-NMR spectra could be reliably covered by this level of theory.[13]

Summary

Introduction

Conformational flexibility is an intrinsic trait of most organic compounds.[1]. The remarkable ability of molecules to adopt multiple possible conformations is usually accompanied by a defined preference for certain of those conformations, a property that resides at the core of molecular interactions and molecular recognition.[2]. We present experimental and computational evidence for an unusual intramolecular hydrogen bonding interaction in a series of N-acyloxazolidinones and other α-acylmethane derivatives, with striking consequences to their NMR spectroscopic properties.

Results

Conclusion