One-Pot Synthesis of Symmetrical and Asymmetrical 3-Amino Diynes via Cu(I)-Catalyzed Reaction of Enaminones with Terminal Alkynes

Abstract

An economical and efficient protocol for the direct construction of amino skipped diynes through the Cu­(I)-catalyzed reaction of enaminones and terminal alkynes has been described. Different kinds of symmetrical and asymmetrical 3-amino diynes could be obtained in up to 83% yield through a one-pot reaction under mild conditions.

Synthesis of Indolizines via Tf2O-Mediated Cascade Reaction of Pyridyl-enaminones with Thiophenols/Thioalcohols

“…According to these results and previous works, ,, a plausible reaction mechanism for this Tf 2 O-mediated cascade reaction was tentatively proposed (Scheme ). Tf 2 O played the role of in situ activation of pyridyl-enaminone 1a to form the highly active vinyl iminium triflate Int-Ia , which successively underwent selective 1,4-addition of thiyl anion ( Int-Ia to Int-II ), triflate anion (TfO – ) removal ( Int-II to Int-III ), and intramolecular cyclization ( Int-III to Int-IV ) processes.…”

“…Subsequently, Huang’s group also realized the synthesis of cyclopentenimines based on Tf 2 O-mediated cascade reaction of secondary amides with potassium organotrifluoroborates (Scheme , eq 3) . Similarly, as versatile building synthons of organic synthesis, enaminones can also be activated in situ by trifluoromethanesulfonic anhydride to generate vinyl iminium triflate Int-I (Scheme , eq 3) . However, selective chemical conversions based on such intermediates have been much less reported.…”

Tf2O‐Mediated Regioselective C(sp2)−H Sulfenylation of Enaminones Using Methyl Sulfoxides as Sulfur Sources

“…However, methyl sulfoxides as sulfur sources were utilized to participate regioselective C(sp 2 )−H sulfenylation of enaminones, which has not been reported yet. After developing the oxidative coupling [11a] and alkynylation [11b] of enaminones, herein, we report the regioselective C(sp 2 )−H sulfenylation of enaminones without metal catalyst and oxidant by using methyl sulfoxides as the sulfur sources (Scheme 1, eq 7).…”

Cobalt Homeostatic Catalysis for Coupling of Enaminones and Oxadiazolones to Quinazolinones

“…. 48 The title compound was obtained as a yellow solid in 48% yield (0.49 g). 1 H NMR (400 MHz, CDCl 3 ) δ 7.83 (dt, J = 8.4, 2.0 Hz, 2H), 7.79 (d, J = 12.4 Hz, 1H), 7.23 (d, J = 8.0 Hz, 2H), 5.71 (d, J = 12.4 Hz, 1H), 3.02 (brd, 6H), 2.68 (q, J = 7.6 Hz, 2H), 1.24 (t, J = 7.6 Hz, 3H).…”