Synthesis of (Z)‐N‐Alkenylazoles and Pyrroloisoquinolines from α‐N‐Azoleketones through Pd‐Catalyzed Tosylhydrazone Cross‐Couplings

Abstract

Scheme 1. Synthesis of Z-trisubstituted olefins by ortho-directed Pd-catalyzed cross-coupling reactions (Ts = tosyl; DG = directing group).Scheme 2. Stereoselective synthesis of N-alkenylazoles and auto-tandem CÀC/CÀC reactions reported in this paper.Scheme 3. Cross-coupling between tosylhydrazone 3 a and nonaflate 2 a and the one-pot reaction from 1 a.

Structurally Diverse π‐Extended Conjugated Polycarbo‐ and Heterocycles through Pd‐Catalyzed Autotandem Cascades

“…Thus, employing 4mol %o f[ Pd 2 (dba) 3 ]a nd tosylhydrazone 1a in excess, the spirocyclic compound 4a derived from the autotandem reactionw as isolated in an excellent yield of 93 %. The structure 4a could be assigned based on the 13 C, 1 HNMR spectrum was ac lear indication of the presence of the endocyclic double bond. Moreover,t he spirocyclic structure was later confirmed by X-ray crystallographic analysisi na nother membero ft his family of spiro compounds (Figure 1).…”

“…Again, both cyclic and acyclict osylhydrazones can be employed in the coupling reaction, leadingt os tructurally diverse polyaromatic structures (Scheme 15). It must be noted that compounds 30 and 33 are expected to be formed as am ixture of two diastereoisomers, which have shown identical 1 Ha nd 13 CNMR spectra in all cases.…”

Palladium-Catalyzed Enantioselective Decarboxylative Allylic Alkylation of Acyclic α-N-Pyrrolyl/Indolyl Ketones

“…5 Hz,1H), 2.89 (ddt, J = 7.9, 2.3, 1.1 Hz, 2H), 2.29 (dq, J = 13.6, 7.5 Hz, 1H), 2.22 -2.11 (m, 1H), 0.75 (t, J = 7.4 Hz, 3H); 19 F NMR (282 MHz, CDCl 3 ) δ -105.6 --105.7 (m); 13 C NMR (125 MHz, CDCl 3 ) δ 197. 4,165.3 (d,J = 254.7 Hz),132.3 (d,J = 3.6 Hz), 131.5 (d, J = 9. 5 Hz), 131.…”

[3+2]‐Cycloaddition for Fully Decorated Vinyl‐1,2,3‐Triazoles: Design, Synthesis and Applications

“…in dioxane at 110°C to furnish 1-(1-(2-bromophenyl)-2-phenylvinyl)-4phenyl-1H-1,2,3-triazole 81 in 55% yield with E : Z ratio 20 : 80 (Scheme 26). [31] In 2015, Das et al revealed a method for the synthesis of 1-VTs by potassium carbonate promoted dehydrohalogenation of 4-aryl-1-(2-haloalkyl)-1H-1,2,3-triazoles 82. In their approach, on treatment of 4-aryl-1-(2-haloalkyl)-1H-1,2,3-triazoles 82 with two equiv.…”