. 2016 Dec 29;82(3):1538–1544. doi: 10.1021/acs.joc.6b02737

Table 2. Experimental and DFT-Computed Isotropic ¹H Hyperfine Couplings (A(¹H) in MHz) for Nitroxides 1 and 2^a.

	(Me)		(vinylic)			(CH₂)^b
	EPR	NMR^c	EPR^d	NMR^c	DFT	EPR^d	NMR^c	DFT
1^e	–	+0.034	1.10	–1.08	–1.68	–	–	–
2	–	+0.058	1.43	–1.26	–1.80	1.09	–1.6	–1.37
		+0.017				1.86		–1.94

DFT computations at the UB3LYP/EPR-III//UB3LYP/6-311G(d,p)+ZPVE level; because no conformational analysis of the methyl groups was carried out, the computed values of A(¹H) for the methyl groups are not reported.

Protons in the CH₂ moiety are diastereotopic.

For paramagnetic ¹H NMR spectra of 1 and 2, see: Figures S15, S16, S24, and S25, SI.

For fluid solution CW EPR spectra of 1 and 2 with spectral simulations, see: Figures S7–S9, SI.

Computed values of A(¹³C) (in MHz) in C₂-symmetric 1 are −16.9 for C1 and C4 (quaternary carbons), +30.5 and +22.2 (avg. = +26.4) for C9–C13 (carbonyl carbons); all other carbons have relatively small values of A(¹³C) ≤ 0.5 MHz, and thus their sidebands are not resolved in the experimental spectrum.

Table 2. Experimental and DFT-Computed Isotropic 1H Hyperfine Couplings (A(1H) in MHz) for Nitroxides 1 and 2a.

Table 2. Experimental and DFT-Computed Isotropic ¹H Hyperfine Couplings (A(¹H) in MHz) for Nitroxides 1 and 2^a.