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An efficient access to novel families of cyano‐containing polyheteroaromatic D−A molecules with extended π‐conjugation, including dibenzo[c,h][1,6]naphthyridine derivatives, has been elaborated. The synthetic strategy is based on the sequence of metal‐catalyzed annulation and cross‐coupling reactions starting from available 4‐ethynyl‐5,6‐difluoro‐7‐(p‐methoxyphenyl)‐2,1,3‐benzothiadiazole to get a new series of isoquinoline‐linked BTD‐based D−A compounds, which further undergo a selective cyanation to afford the corresponding mono‐CN‐ or di‐CN‐BTD derivatives depending on the reaction conditions. In course of the investigation of cyanation process, a new type of intramolecular heterocyclization included the transformation of the benzothiadiazole core into hardly accessible dibenzo[c,h][1,6]naphthyridine framework has been unexpectedly discovered. The protocols developed tolerate a wide range of donor blocks such as diphenylamine, carbazole, dibenzoazepine and dihydroacridine. [ABSTRACT FROM AUTHOR]

An efficient method of accessing new CF3-containing spiro-[indene-proline] derivatives has been developed based on a Cp*Rh(III)-catalyzed tandem C-H activation/[3+2]–annulation reaction of 5-aryl-2-(trifluoromethyl)-3,4-dihydro-2H-pyrrole-2-carboxylates with alkynes. An important feature of this spiro annulation process is the feasibility of dehydroproline moiety to act as a directing group in the selective activation of the aromatic C-H bond. [ABSTRACT FROM AUTHOR]

An efficient method for the selective preparation of new CF3‐substituted α‐amino acid derivatives decorated with pharmacophore pyrimido[1,6‐a]indolone core has been developed via Rh(III)‐catalyzed C−H activation/[4+2]‐annulation of N‐(pivaloyloxy)‐indole‐1‐carboxamides with propargyl‐containing α‐amino carboxylates and α‐amino phosphonates. [ABSTRACT FROM AUTHOR]

A convenient pathway to a new series of α-CF3-substituted α-amino acid derivatives bearing pharmacophore isoquinolone core in their backbone has been developed. The method is based on [4+2]-annulation of N-(pivaloyloxy) aryl amides with orthogonally protected internal acetylene-containing α-amino carboxylates under Rh(III)-catalysis. The target annulation products can be easily transformed into valuable isoquinoline derivatives via a successive aromatization/cross-coupling operation. [ABSTRACT FROM AUTHOR]

An efficient pathway to a new family of fluorinated polyheteroaromatic D‐A molecules has been developed. The method is based on the Rh(III)‐catalyzed regioselective [4+2]‐annulation of N‐(pivaloyloxy)‐benzamides with 4‐ethynyl‐5,6‐difluoro‐7‐(p‐methoxyphenyl)‐2,1,3‐benzothiadiazole as a key step followed by the aromatization/Suzuki coupling sequence to furnish the target D‐A systems with modifiable acceptor block. The discovered difference in reactivity between ArB(OH)2 and ArBPin allows performing a divergent modification of BTD acceptor block by the manipulation of aryl boronic reagents in the ortho‐selective C−F activation of the fluorinated BTD moiety under Suzuki reaction conditions to furnish new D1‐π‐A‐D2 systems in good yields. Such step‐by‐step modification of the acceptor block has been achieved by Pd‐catalyzed C−F bond activation under isoquinoline ring assistance for the first time. [ABSTRACT FROM AUTHOR]

An efficient way to access highly functionalized proline derivatives was developed based on a Cu(I)-catalyzed reaction between CF3-substituted allenynes and tosylazide, which involved a cascade of [3 + 2]-cycloaddition/ketenimine and a rearrangement/Alder-ene cyclization to afford the new proline framework with a high diastereoselectivity. [ABSTRACT FROM AUTHOR]

An efficient method for the selective preparation of trifluoromethyl-substituted azepin-2-carboxylates and their phosphorous analogues has been developed via Cu(I)-catalyzed tandem amination/cyclization reaction of functionalized allenynes with primary and secondary amines. [ABSTRACT FROM AUTHOR]

An efficient strategy for the preparation of a novel series of benzothiadiazole‐containing isoquinoline‐bridged D‐A compounds based on Cp*Rh(III)‐catalyzed redox‐neutral annulation of N‐(pivaloyloxy)‐benzamides with 4‐ethynyl‐7‐(p‐methoxyphenyl)‐2,1,3‐benzothiadiazole as a key step followed by the installation of donor units, such as diphenylamine, carbazole, and dihydrodibenzoazepine, by aromatization and Suzuki coupling reactions, has been developed. An initial photophysical, electrochemical and DFT investigations of the selected products have been performed. [ABSTRACT FROM AUTHOR]

A series of new orthogonally protected α‐CF3‐substituted α‐amino carboxylates, and α‐amino phosphonates decorated with pharmacophore isoquinolone core has been elaborated through the Rh(III)‐catalyzed C−H activation/annulation of aryl hydroxamates with propargyl‐containing α‐amino acid derivatives and their phosphorus analogues. [ABSTRACT FROM AUTHOR]

[Display omitted] An efficient and selective access to novel α-CF 3 -substituted γ,δ-didehydro lysine derivatives and their phosphorus analogues has been developed via the Cu-catalyzed Mannich reaction of α-amino α-propargyl α-trifluoromethyl carboxylates or phosphonates with different secondary amines and paraformaldehyde. [ABSTRACT FROM AUTHOR]

Functionally substituted indole derivatives are important intermediates for the synthesis of new potential drug candidates exhibiting strong bioactivities. Over the past few years, significant progress has been made in the direct C-H functionalization of the indole ring through the usage of metal-catalyzed intermolecular cross-coupling with diazo compounds. Directing group strategy provides a unique possibility for selective insertion of carbenes catalytically generated from diazo compounds into challenging indole C2-H and C7-H bonds. This short review summarizes recent advances in carbenoid functionalization of indole derivatives under chelation-controlled metal catalysis. 1 Introduction 2 Indole C2 Alkylation with a-Diazotized Meldrum's Acid 3 Indole C2 Alkylation with Diazomalonate Derivatives and Related Compounds 4 Indole C7 Alkylation with Diazomalonates and Related Compounds 5 Tandem Indole C2-H Alkylation/Cyclization 6 Indoline C7 Alkylation with Diazomalonates and Related Compounds 7 Tandem Indoline C7-H Alkylation/Cyclization 8 Conclusion. [ABSTRACT FROM AUTHOR]

An efficient method for the CF3-carbenoid C-7 functionalization of N-pyrimidylindolines has been developed. This protocol uses readily available methyl 3,3,3-trifluoro-2-diazopropionate as a cross-coupling partner and smoothly proceeds under chelation-controlled RhIII catalysis. The reactions provide the indoline products with high regioselectivity within a few hours and allow for the introduction of both the CF3 and carboxylate functions at the C-7 position. [ABSTRACT FROM AUTHOR]

An efficient method for the CF3-carbenoid C-H functionalization of benzenes and indoles using readily available methyl 3,3,3-trifluoro-2-diazopropionate as a cross-coupling partner under chelation-controlled RhIII catalysis has been developed. The reactions proceeded smoothly with high regioselectivity in a few hours and allowed the simultaneous introduction of CF3 and carboxylate functions into the 2-position of directing-group-containing benzenes and indoles. [ABSTRACT FROM AUTHOR]

An efficient protocol for the direct CH-functionalization of indole and its derivatives has been developed by using Cu(F3-acac)2-catalyzed insertion of CF3-carbene derived from methyl 3,3,3-trifluoro-2-diazopropionate. The reaction proceeds with high regioselectivity within a few minutes under low catalyst loading and allows the introduction of CF3 and carboxylate functions simultaneously into the 3- or 2-position of the indole core. This method can be successfully applied for the synthesis of trifluoromethyl-containing paullones, which are new members of the known family of potent inhibitors of cyclin-dependent kinases. [ABSTRACT FROM AUTHOR]

An efficient access to novel trifluoromethyl-substituted phosphonate analogues of 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (TIC) derivatives based on regioselective rutheniumcatalyzed co-cyclotrimerization of functionalized 1,7-diynes with various alkynes has been developed using RuClCp"cod and preferably Grubbs second-generation catalysts. [ABSTRACT FROM AUTHOR]

Abstract: A convenient synthetic pathway to novel functionalized tetrapeptides containing the 1,2,3-triazole moiety is described. The target molecules were obtained by the reaction of fluorinated α-amino acids or α-aminophosphonates with azidopeptides via Cu(I)-catalyzed Huisgen cycloaddition reaction (click chemistry). The synthesized tetrapeptides may find important applications in biomedical chemistry as potential drugs. [Copyright &y& Elsevier]

A simple and convenient method for the incorporation of fluorinated α-hydroxy acids into peptides is described. The target conjugates were obtained from α-alkynyl-α-trifluoromethyl-α-hydroxy acids and azido peptides via the copper(I)-catalyzed Huisgen cycloaddition reaction (click chemistry). After straightforward deprotection, the α-trifluoromethyl-α-hydroxy acid containing peptides may find important applications in biochemistry and medicinal chemistry. [ABSTRACT FROM AUTHOR]

Abstract: A new efficient access to functionalized CF3-substituted and nitrogen or sulfur-containing heterocycles has been developed directly from diazocompounds CF3C(N2)Z (Z=CO2Me, P(O)(OEt)2). The method is based on the direct selective synthesis of doubly unsaturated substrates followed by metal-mediated carbocylization. The first step has been performed by Cu(II)-catalyzed [2,3]-sigmatropic rearrangement of propargyl- or/and allyl-containing sulfur and nitrogen ylides leading to fluorinated enynes, diolefins, and especially allenynes derivatives. The second step involves their carbocyclization via ring closing metathesis and Pauson–Khand reaction. [Copyright &y& Elsevier]

Abstract: A convenient method for the preparation of α-CF3-α-aminophosphonates bearing alkynyl group at the α-carbon atom has been described. New alkynylphosphonates have been further utilized in the synthesis of functionalized triazole-containing α-CF3-α-aminophosphonates via copper-catalyzed (3+2)-cycloaddition to different organic azides. [Copyright &y& Elsevier]

The title reaction allows the regioselective introduction of CF3 and carboxylate functions into the 2- or 3-position of the indole core. [ABSTRACT FROM AUTHOR]