NMR spectra of substituted alpha-aminonitrilecyclohexane mixtures.

Published: 13 August 2023| Version 1 | DOI: 10.17632/x97s9ypxjz.1
Contributor:
John Krstenansky

Description

The NMR spectra of product mixtures resulting from the reaction of substituted cyclohexanones with an amine hydrochloride and potassium cyanide in water. The resulting products exhibit a preference for one of the two possible geometric isomers due to diastereofacial selectivity during the attack by the cyanide ion on the intermediate iminium. A pdf file is included as a key to the identity of the folders containing the NMR data on the individual compounds.

Files

Steps to reproduce

General procedure: 1 eq. of the starting ketone was stirred in water with 1 eq. substituted amine at room temperature. To this mixture 1.05 eq. potassium cyanide was added and the mixture was stirred overnight. The mixture was extracted with dichloromethane, the layers separated, the organic layer dried over anhydrous sodium sulfate, and evaporated in vacuo. Approximately, 20mg of the dried extract was dissolved in 0.60 mL CDCl3 containing 0.1% TMS (Cambridge Isotopes, Tewksbury, MA). These samples were then submitted for NMR spectroscopy ((1H, 13C, HSQCAD, gHMBCAD, DEPT, gCOSY). 1D and 2D NMR spectra (1H, 13C) were recorded in CDCl3 at 300 K using a Varian 400 MHz MR spectrometer equipped with a AutoX DB broadband probe. Pulse sequences and acquisition were accomplished using VnmrJ software (VnmrJ 4.2, Ag-ilent Technologies, Santa Clara, CA). Data processing was achieved using ACD/Spectrus Processor version 2017.2. Chemical shifts are reported in parts per million (ppm, δ) NMR relative to tetramethylsilane (δ 0.00 ppm). 1H NMR splitting patterns are designated as singlet (s), doublet (d), triplet (t), doublet of doublets (dd), doublet of doublets of doublets (ddd), doublet of triplets (dt), doublet of quadruplets (dq), multiplet (m) or broad (br). – Add any other splitting patterns you use here. Coupling constants (J) are reported in Hertz (Hz). The 13C, HSQCAD (optimized for 146 Hz 1-bond CH coupling), gHMBCAD (opti-mized for multiple-bond coupling = 8 Hz), DEPT (optimized for 1-bond coupling of 146 Hz), and gCOSY pulse sequences were used without any change to the Varian standard parameters. Two-dimensional spectra were collected using non-uniform sampling with a 50% sampling rate.

Institutions

Keck Graduate Institute

Categories

Stereochemistry, Nuclear Magnetic Resonance Spectroscopy, Selectivity

Funding

National Institute of Justice

2016‐R2‐CX‐0059

Licence