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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]

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]

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]

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]

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]

The synthesis of the title compounds is achieved through N-propargylation of substrates (I) and (VIII) followed by cyclotrimerization with alkynes. [ABSTRACT FROM AUTHOR]