Modular synthesis of mono, di, and tri-1,4-disubstituted-1,2,3-triazoles through copper-mediated alkyne–azide cycloaddition

AbstractThe synthesis of 1,2,3-triazoles was developed employing sequential copper azide–alkyne cycloaddition, tosylation, sodium azide, and copper azide–alkyne steps. This approach allowed the synthesis of two and three 1,2,3-triazole rings. A preliminary study to gain further insight into the reaction was performed using in situ ReactIR technology

Synthesis of 1,3-diynes via detelluration of bis(ethynyl)tellurides

The synthesis of symmetric conjugated diyne systems with electron-withdrawing or electron-donating substituents via a palladium-catalyzed detelluration of bis(arylethynyl)tellurides and bis(alkylethynyl)tellurides is described. This procedure is effected under atmospheric conditions in DMF using Pd(OAc)2 as a catalyst and AgOAc as an additive in the presence of triethylamine. This route offers efficient access to conjugated diyne systems in short reaction time. X-ray crystallographic structure and solid-state conformation of bis(p-tolylethynyl)telluride show a supramolecular chain aligned along the b axis, sustained by C-H...π interactions.Neste artigo é descrita a síntese de sistemas diínicos conjugados contendo substituintes elétronatratores e elétron-doadores via a deteluração catalizada por paládio de bis-(ariletinil)teluretos e bis-(alquiletinil)teluretos. Este procedimento foi realizado sob condições atmosféricas em DMF usando Pd(Oac)2 como catalisador e AgOAc como um aditivo na presença de trietilamina. Esta rota oferece acesso eficiente a sistemas diínicos conjugados em um curto período de tempo. A estrutura cristalográfica por difração de raios X do telureto de bis(p-toluiletinila) e a conformação no estado sólido mostram uma cadeia supramolecular alinhada ao longo do eixo b, sustentada por interações CH...π.FAPESPCNP

5-(4-Fluoro­phen­yl)-2,2,6-trimethyl-4H-1,3-dioxin-4-one

The 1,3-dioxine ring in the title compound, C13H13FO3, is in a half-boat conformation with the methyl-bonded C atom 0.612 (2) Å out of the plane defined by the remaining five atoms

Crystal structure of [(2R,3R,4S)-3,4-bis-(acetyloxy)-5-iodo-3,4-dihydro-2H-pyran-2-yl]methyl acetate

Acknowledgements We thank Professor Regina H. A. Santos from IQSC–USP for the X-ray data collection. The Brazilian agencies CNPq (305626/2013–2 to JZS; 306121/2013-2 to IC; 308320/2010-7 to HAS) and FAPESP are acknowledged for financial support.Peer reviewedPublisher PD

Crystal structure of 5-(1,3-dithian-2-yl)-2H-1,3-benzodioxole

We thank Professor Regina H. A. Santos from IQSC–USP for the X-ray data collection. The Brazilian agencies CNPq (305626/2013-2 to JZS, 306121/2013-2 to IC and 308320/2010-7 to HAS), FAPESP (2012/00424-2 and 2013/21925-2) and CAPES are acknowledged for financial support.Peer reviewedPublisher PD

Structural systematics of aryl-1,3-dithiane derivatives: crystal and energy-minimised structures, and Hirshfeld surface analysis

The crystal structure analysis of three aryl-1,3-dithiane derivatives, with aryl=4-methylphenyl (1), 4-chlorophenyl (2) and 2,4-dichlorophenyl (3), shows the three molecules to have very similar conformations, with the aryl ring lying on an approximate mirror plane that bisects the dithiane ring which adopts a chair conformation; the energy-minimised structures are consistent with the experimental structures. The greater barrier to rotation about the methine-C–C(ipso) bond in 3, cf. 1 and 2, is related to unfavourable intramolecular S···Cl interactions in the putative transition state. The molecular packing in 1–3, while globally similar, are distinct, being based on combinations of identifiable C–H···π(arene), C–H···S and C–Cl···π(arene) interactions. The lack of isostructural relationships points to the significance of the identified intermolecular interactions to direct molecular packing

2,2,6-Trimethyl-5-[2-(4-methyl­phen­yl)ethyn­yl]-4H-1,3-dioxin-4-one

The 1,3-dioxin-4-one ring in the title compound, C16H16O3, is in a half-boat conformation with the quaternary O—C(CH3)2—O atom lying 0.546 (1) Å out of the plane defined by the remaining five atoms. The crystal structure is consolidated by C—H⋯O contacts that lead to supra­molecular layers

Potassium trifluoro­[(Z)-3-methoxy­prop-1-en­yl]borate

In the title salt, K+·C4H7BF3O−, the K atom is surrounded by six anions making close contacts through seven F [K⋯F = 2.779 (1)–3.048 (1) Å] and two O [K⋯O = 2.953 (2) and 3.127 (2) Å] atoms in a trivacant fac-vIC-9 icosa­hedral coordination geometry

1-[(Z)-1-Bromo-2-(butyl­dichloro-λ4-tellan­yl)ethen­yl]cyclo­hex-1-ene

The TeIV atom in the title compound, [Te(C4H9)(C8H10Br)Cl2] or C12H19BrCl2Te, is in a distorted ψ-trigonal–bipyramidal geometry, with the lone pair of electrons projected to occupy a position in the equatorial plane, and with the Cl atoms being mutually trans [172.48 (4)°]. Close intra­molecular [Te⋯Br = 3.3444 (18) Å] and inter­molecular [Te⋯Cl = 3.675 (3) Å] inter­actions are observed. The latter lead to centrosymmetric dimers which assemble into layers in the bc plane. The primary connections between layers are of the type C—H⋯Cl

1-[(Z)-2-Butyl­tellan­yl-1-chloro­ethen­yl]­cyclo­hex-1-ene

The TeII atom in the title mol­ecule, C12H19ClTe, is coordinated in a V-shaped geometry by C atoms derived from the disparate organic substituents. A short intramolecular C—H⋯Cl contact occurs owing to the proximity of the ethene bond in the six-membered ring to the Cl atom. In the crystal, mol­ecules assemble into layers parallel to the ac plane, with the closest inter­actions between them being of the Te⋯Te type [3.9993 (16) Å]