21969-11-9Relevant articles and documents
NMR Study of Substituent Effects in 4-Substituted and 4,4'-Disubstituted Diphenyl Sulphides
Chandrasekaran, R.,Perumal, S.,Wilson, D.A.
, p. 1001 - 1006 (1987)
The proton and carbon NMR spectra of nine 4-X-diphenyl sulphides (series 1), seven 4-X-4'-NO2-diphenyl sulphides (series 2) and eight 4,4'-X2-diphenyl sulphides (series 3) have been obtained.Correlation of the 13C chemical shifts with the appropriate substituent chemical shifts (SCS) for monosubstituted benzenes (Lynch plots) show an enhancement of substituent effect at C-1 (carbon para to the substituent) in series 1 ans 2, but not in series 3.The carbons of the unsubstituted ring in series 1 also correlate with Cp-SCS, with slopes of less than unity; correlation for C-1' has a negative slope.Dual substituent parameter (DSP) correlations of the 13C chemical shifts with ?I/?oR are good to exellent for all the carbons of series 1 compounds, except those ortho to the substituent X.The carbons meta to the substituent X correlate well, but with negative values for ρI and ρR, although showing a scattered Lynch plot.Similar correlations are found with some carbon shifts in series 2, and with C-1 shifts in series 3.It is concluded that (a) reverse resonance effects are operative at the position meta to the variable substituent by virtue of the sulphur substituent ortho to that carbon; (b) there is transmission of inductive (field) and resonance effects from one aryl ring to the other, except when both rings carry substituents of the same electronic character (series 3); (c) there is some evidence for ?-polarization in the unsubstituted phenyl ring of series 1 compounds.Key words 1H NMR 13C NMR Diphenyl sulphides substituent effects
Nucleophilic aromatic substitution reactions under aqueous, mild conditions using polymeric additive HPMC
Ansari, Tharique N.,Borlinghaus, Niginia,Braje, Leon H.,Braje, Wilfried M.,Handa, Sachin,Ogulu, Deborah,Wittmann, Valentin
supporting information, p. 3955 - 3962 (2021/06/17)
The use of the inexpensive, benign, and sustainable polymer, hydroxypropyl methylcellulose (HPMC), in water enables nucleophilic aromatic subsitution (SNAr) reactions between various nucleophiles and electrophiles. The mild reaction conditions facilitate a broad functional group tolerance that can be utilized for subsequent derivatization for the synthesis of pharmaceutically relevant building blocks. The use of only equimolar amounts of all reagents and water as reaction solvent reveals the greenness and sustainability of the methodology presented herein.
An Iodide-Mediated Transition-Metal-Free Strategy towards Unsymmetrical Diaryl Sulfides via Arylhydrazines and Thiols
Asadpour, Mohammad,Azizzade, Meysam,Ghasemi, Mehran,Jafarpour, Farnaz,Rajai-Daryasarei, Saideh
supporting information, p. 727 - 734 (2020/02/25)
A mild, scalable iodine-mediated oxidative cross-coupling reaction of arylhydrazines and thiols for construction of thioethers (sulfides) in the absence of any transition metals or photocatalysts is disclosed. A variety of unsymmetrical diaryl sulfides with broad substrate scope both on thiols and hydrazines were synthesized in high yields in water at room temperature. Furthermore, to demonstrate the utility of the protocol, the above C-S bond formation was applied in the synthesis of the key structure of vortioxetine as an antidepressant drug. The gram-scale outcome also added to the potential utility of this protocol.