N-Arylation of DABCO with Diaryliodonium Salts: General Synthesis of N-Aryl-DABCO Salts as Precursors for 1,4-Disubstituted Piperazines

Abstract

Employing DABCO as a substrate, aryl(mesityl)iodonium triflates are introduced as arylating agents for a tertiary sp 3 -nitrogen. Mild conditions and exceptional selectivity of the aryl group transfer allow unprecedented N-aryl-DABCO salts to be obtained, bearing substituents of different electronic natures. This metal-free methodology has no analogy among known transition-metal-based reactions. The utility of isolated N-aryl-DABCO salts is demonstrated for the preparation of flibanserin.

Reactions of PhIX2 I(iii) oxidants with heavy triphenyl pnictines

“…The reaction of Ph3Sb with PhI(OAc)2 has been previously reported to oxidize the antimony and give the expected diacetoxy Sb(V) complex. 26 Colourless crystals were obtained and X-ray diffraction studies showed via unit cell analysis 27 the result was a diaryliodonium triflate salt 13 (Scheme 11) with 1 H NMR of the crystals also matching literature reports. 28 Compound 13 has been synthesised via numerous different methods one of which is known to involve a diarylstannane reagent.…”

Reactions of PhIX2 I(III) Oxidants with Heavy Triphenyl Pnictines

“…Colourless crystals were obtained and X-ray diffraction studies showed via unit cell analysis 27 the result was a diaryliodonium triflate salt 13 (Scheme 11) with 1 H NMR of the crystals also matching literature reports. 28 Compound 13 has been synthesised via numerous different methods one of which is known to involve a diarylstannane reagent.…”

DABCO bond cleavage for the synthesis of piperazine derivatives

“…Recently, Karchava et al introduced the diaryliodonium salts 94 as efficient arylating agents for a tertiary sp 3 -nitrogen. 46 For this purpose, reaction of DABCO 1 (1 equiv.) with various aryl(mesityl)iodonium triflates 94 (2 equiv.)…”