Synthesis of disulfides tethered pyrroles from β-ketothioamides via a bicyclization/ring-opening/oxidative coupling reaction
作者:Cong-Xiang Li、Rui-Juan Liu、Kun Yin、Li-Rong Wen、Ming Li
DOI:10.1039/c7ob00655a
日期:——
A DABCO-promoted three-component reaction of β-ketothioamides (KTAs), arylglyoxals and 2-cyanoacetates to access disulfides tethered pyrroles by air as oxidant has been disclosed. Importantly, this protocolinvolves a tandem sequence that includes Knoevenagel condensation, Michaeladdition, N-cyclization, O-cyclization, ring-opening and oxidative coupling.
Herein, we unveiled the novel approach for the synthesis of α-oxoketene S,S- and N,S-acetals employing a Mitsunobuprotocol. A wide range of alcohols has been successfully utilized, enabling great tolerability to this reaction. A diverse set of β-keto(dithioesters/thioamides) bearing various functional groups were found to be well suited substrates for this reaction, showing no obvious electronic effect
Rhodium(II)-Catalyzed Annulative Coupling of β-Ketothioamides with α-Diazo Compounds: Access to Highly Functionalized Thiazolidin-4-ones and Thiazolines
An operationally simple and efficient one-pot protocol for the synthesis of highly functionalized thiazolidin-4-ones and thiazolines has been devised via Rh(OAc)2-catalyzed annulative coupling of β-ketothioamides with diazo compounds under mild reaction conditions for the first time. This double functionalization of diazo compounds proceeds via selective S-alkylation followed by intramolecular N-cyclization
Three-Component Cascade Annulation of β-Ketothioamides Promoted by CF<sub>3</sub>CH<sub>2</sub>OH: A Regioselective Synthesis of Tetrasubstituted Thiophenes
作者:Li-Rong Wen、Tao He、Ming-Chao Lan、Ming Li
DOI:10.1021/jo401397d
日期:2013.11.1
A rapid and highly efficient method for the regioselective synthesis of thiophene derivatives has been developed by annulation of β-ketothioamides with arylglyoxals and 5,5-dimethyl-1,3-cyclohexanedione in CF3CH2OH within 15 min. The present synthesis has several desirable features, such as high regioselectivity, a concise one-pot protocol, short reaction time, and easy purification. This methodology
Visible‐Light‐Driven Photocatalyst‐ and Additive‐Free Cross‐Coupling of β‐Ketothioamides with α‐Diazo 1,3‐Diketones: Access to Highly Functionalized Thiazolines
photocatalyst‐ and additive‐free, visible‐light‐mediated chemoselective domino protocol was devised to access fully substituted thiazoline derivatives from β‐ketothioamides and α‐diazo 1,3‐diketones at moderate temperature in open air. The reaction proceeds through in situ generation of electrophilic carbenes from α‐diazo 1,3‐diketones by a low‐energy blue LED (448 nm), which undergoes selective coupling