960化工网
Solid-state NMR and computational studies of tetratolyl urea calix[4]arene inclusion compounds
Chulsoon Moon,Gunther Brunklaus,Daniel Sebastiani,Yuliya Rudzevich,Volker Böhmer,Hans Wolfgang Spiess
Physical Chemistry Chemical Physics Pub Date : 08/17/2009 00:00:00 , DOI:10.1039/B822535D
Abstract

Solid-state guest dynamics of tetratolyl tetraurea calix[4]arene tetrapentylether dimeric capsules filled with different types of aromatic guests such as benzene-d6, fluorobenzene-d5 and 1,4-difluorobenzene were studied. Upon inclusion, all guest moieties revealed complexation-induced shifts varying from 2.8 ppm to 5.1 ppm. All guest molecules were shown to undergo distinct motions, ranging from mere C6-rotations of benzene-d6 to (ill-defined) 180° phenyl flips of fluorobenzene-d5. In all cases, dynamic heterogeneities were identified based on 2H lineshape deconvolution. In addition, by combination of both a computed nucleus independent chemical shift (NICS) map and explicit 19F and 2H ab initio DFT chemical shift calculations, the preferred orientation of the guest molecules within the host was derived.

Graphical abstract: Solid-state NMR and computational studies of tetratolyl urea calix[4]arene inclusion compounds
平台客服
平台客服
平台在线客服