Transition-metal and base-free thioannulation of propynamides with sodium sulfide and dichloromethane for the selective synthesis of 1,3-thiazin-4-ones and thiazolidine-4-ones
A thioannulation of propynamides with sodium sulfide and CH2Cl2 in the absence of transition-metal and base has been established. This one-pot tandem reaction provides a facile and efficient method for the selective synthesis of 1,3-thiazide-4-ones or thiazolidine-4-ones through constructing both C–N and C–S bonds. The atom-economic reaction features mild conditions and good functional group tolerance
Reactions of <i>N</i>,3-diarylpropiolamides with arenes under superelectrophilic activation: synthesis of 4,4-diaryl-3,4-dihydroquinolin-2(1<i>H</i>)-ones and their derivatives
作者:Larisa Yu Gurskaya、Diana S Belyanskaya、Dmitry S Ryabukhin、Denis I Nilov、Irina A Boyarskaya、Aleksander V Vasilyev
DOI:10.3762/bjoc.12.93
日期:——
The reaction of 3-aryl-N-(aryl)propiolamides with arenes in TfOH at room temperature for 0.5 h led to 4,4-diaryl-3,4-dihydroquinolin-2-(1H)-ones in yields of 44-98%. The obtained dihydroquinolinones were further transformed into the corresponding N-acyl or N-formyl derivatives. For the latter, the superelectrophilic activation of the N-formyl group by TfOH in the reaction with benzene resulted in the
A facile protocol for the tunable synthesis of 10-hydroxy-1-azaspiro[4.5]deca-3,6,8-trien-2-ones and benzo[b]pyrrolo[2,1-c][1,4]oxazin-3-ones is described. A tunable synthesis has been realized by the use of ZnBr2/oxone and tetra-n-butylammonium bromide (TBAB)/oxone. The reaction proceeds smoothly with high efficiency and a broad substrate scope. Mechanistic studies indicate that an N-protecting group-assisted
Time-Economical Radical Cascade Cyclization/Haloazidation of 1,6-Enynes: Construction of Highly Functional Succinimide Derivatives
作者:Yan Gu、Lei Dai、Kaimin Mao、Jinghang Zhang、Chang Wang、Liming Zhao、Liangce Rong
DOI:10.1021/acs.orglett.0c00682
日期:2020.4.17
A “time-economical” radical cascade cyclization/haloazidation of 1,6-enynes provides a direct approach to access highlyfunctional succinimide compounds. Moderate to excellent yields along with excellent Z/E ratio were obtained under the reaction features of broad substrate scope, good functional group tolerance, and mild reaction conditions.
We describe herein a general approach to napthyridinones via the Pd-catalyzed annulation of 1,6-enynes with 2-iodoanilines. This protocol represents a rare carbo-aminative annulative cyclization via the 6-endo-trig mode, subduing the well-documented exo-trig/dig cyclizations. The regioselective aryl palladation of alkyne followed by Heck-type intramolecular coupling before isomerization were key in