2049-96-9Relevant articles and documents
CH-π Interaction as an Important Driving Force of Host-Guest Complexation. Further Evidence for the Selective Incorporation of Alkyl Groups in the Polyhydroxy Aromatic Cavity of Calix[4]resorcarene Host
Kikuchi, Yasuaki,Aoyama, Yasuhiro
, p. 217 - 220 (1996)
The complexation of a calix[4]resorcarene host (2,8,14,20-tetraundecylcalix[4]arene-4,6,10,12,16,18,22,24-octol) with borneol in benzene or alkylbenzene was investigated by circular dichroism (CD) spectroscopy. The binding constants are dramatically solvent-dependent and decrease with respect to the substituents on the benzene ring in the order H>methyl>ethyl>propyl>butyl. The complexation of the same host with alkyl benzoates in limonene as a chiral hydrocarbon solvent was readily monitored by following their competitive inhibition effects on the CD intensities, reflecting the chiral host-solvent interaction. The binding constants for alkyl benzoates were again highly dependent on the alkyl groups, and changed in the order decylhexylmethylpropyl≈pentyl?butyl. There is thus an optimal chain length at butyl. These results provide further evidence for the selective incorporation of alkyl groups in the polyhydroxy aromatic cavity of the host.
Electrochemical esterification via oxidative coupling of aldehydes and alcohols
Smeyne, Dylan,Verboom, Katherine,Bryan, Maria,LoBue, James,Shaikh, Abid
supporting information, (2021/03/26)
An electrolytic method for the direct oxidative coupling of aldehydes with alcohols to produce esters is described. Our method involves anodic oxidation in presence of TBAF as supporting electrolyte in an undivided electrochemical cell equipped with graphite electrodes. This method successfully couples a wide range of alcohols to benzaldehydes with yields ranging from 70 to 90%. The protocol is easy to perform at a constant voltage conditions and offers a sustainable alternative over conventional methods.
Erratum: Ruthenium-catalyzed C-H hydroxylation in aqueous acid enables selective functionalization of amine derivatives (Journal of the American Chemical Society (2017) 139:28 (9503-9506) DOI: 10.1021/jacs.7b05469)
Mack, James B.C.,Gipson, John D.,Du Bois,Sigman, Matthew S.
supporting information, p. 3016 - 3016 (2021/03/01)
Page 9504. The structure of product 3cc in Table 2 was found to be mis-assigned. We thank Prof. Phil Baran and Dr. Rafael Navratil for bringing this error to our attention. The correct structure contains an additional benzylic alcohol at the C-9 position of the steroid (3cc′, shown below). With the accompanying change in molecular weight, the isolated yield is 29%. Supporting Information. The incorrect structure and yield also appeared on pages S20 and S84 in the SI. Given this, the HRMS entry on page S20 should read as follows: “HRMS (ESI-TOF) m/z calcd for C19H18F3O5S+ (M-O+Na)+ 415.0822, found 415.0857”. The complete corrected SI is provided here.
