Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia , Via Elce di Sotto 8, I-06123 Perugia, Italy.
J Am Chem Soc. 2014 Jan 8;136(1):112-5. doi: 10.1021/ja4119169. Epub 2013 Dec 27.
(19)F,(1)H HOESY, diffusion, and temperature-dependent (19)F and (1)H NMR studies allowed us to unequivocally probe the association between the frustrated PR3/B(C6F5)3 (1, R = CMe3; 2, R = 2,4,6-Me3C6H2) Lewis pairs in aromatic solvents. No preferential orientation is favored, as deduced by combining (19)F,(1)H HOESY and DFT results, suggesting association via weak dispersion rather than residual acid/base interactions. The association process is slightly endoergonic [K = 0.5 M(-1), ΔG(0)(298 K) = +0.4 kcal/mol for 2], as derived from diffusion NMR measurements.
(19)F,(1)H HOESY、扩散和温度依赖的 (19)F 和 (1)H NMR 研究使我们能够明确探测受阻 PR3/B(C6F5)3（1，R = CMe3；2，R = 2,4,6-Me3C6H2）路易斯对在芳香溶剂中的缔合。结合 (19)F,(1)H HOESY 和 DFT 结果，没有优先取向的优势，表明通过弱色散而不是残余酸碱相互作用进行缔合。缔合过程略微是吸热的[K = 0.5 M(-1)，对于 2，ΔG(0)(298 K) = +0.4 kcal/mol]，如从扩散 NMR 测量中得出的。
