Copper-Catalyzed Trifluoromethylselenolation of Aryl and Alkyl Halides: The Silver Effect in Transmetalation

Abstract

A catalytic trifluoromethylselenolation of aryl and alkyl halides by a Cu(I) catalyst has been developed. A key intermediate, [(phen)Cu(SeCF3)]2 (5) was successfully isolated and characterized by X-ray diffraction. The important role of silver in the transmetalation process during the catalytic cycle was elucidated. A wide range of trifluoromethylselanes have been prepared from readily available starting materials from a method that tolerates various important functional groups.

Alkynyl trifluoromethyl selenide synthesis via oxidative trifluoromethylselenolation of terminal alkynes

“…[46][47][48][49][50][51][52] The organoselenium compounds also display significant potential as antioxidant, antitumor, antimicrobial, and antiviral agents. 58 Since no method is available in literature for synthesis of trifluoromethylselenolated acetylenes, we developed a novel method to access them. 21 These organic halides were reacted smoothly with 1 to furnish the corresponding trifluoromethylselenolated products in good yield (Scheme 1).…”

Copper-promoted/copper-catalyzed trifluoromethylselenolation reactions

“…In 2014, Hor and Weng reported the trifluoromethylselenolation of (hetero)aryl iodides and alkyl bromides with the Ruppert-Prakash reagent, TMSCF 3 , elemental selenium, potassium fluoride, and silver carbonate under copper catalysis (Scheme 15, conditions I) [39]. Mechanistically, the authors proposed the formation of a silver(I)-SeCF 3 adduct, followed by a transmetallation step, yielding the active CuSeCF 3 species.…”

Computational insights into the coupling mechanism of benzoic acid, phenoxy acetylene and dihydroisoquinoline catalyzed by silver ion as polarizer and stabilizer

“…The results show that, from IM5 via TS3 to P, the bond order of the newly-formed C-N bond is increased from 0.082 via 0.919 to 1.302. So in P, this C-N bond contains appreciable π bonding because the N atom links to the carboxyl carbon to form a Π 4 3 delocalized bond. Meanwhile, the C=N bond, whose bond order is decreased from 1.994 via 1.733 to 1.066, is reduced to a single bond for the M06-2X method predicts that the atomic polar tensor (APT) derived charge [58,59] on N is abated significantly from −0.686 e via − 0.881 e to −1.002 e. The energy barrier calculated from the M06-L and M06-2X functionals (72.5 kJ/mol vs 82.7 kJ/mol) is much lower than that of the rate-determining step via TS1-a, so when stabilized by Ag + , the α-acyloxy enol ester intermediate IM4-a will readily add to the C=N double bond of dihydroisoquinoline to form P. Figure 5 shows P to be a very stable species with a relative free energy of −263.5 kJ/mol (−278.8 kJ/mol acquired from the M06-2X method).…”