Dimethyl 11,13-dimethyl-16-[1,2-bis­(methoxy­carbon­yl)ethen­yl]-12-oxo-16,17-dioxa-18-aza­hexa­cyclo­[7.5.1.11,4.16,9.110,14.05,15]octa­deca-2,7-diene-2,3-dicarboxyl­ate

The title compound, C27H29NO11, is a product of the tandem ‘domino’ Diels–Alder reaction. The mol­ecule comprises a fused hexa­cyclic system containing four five-membered rings (two dihydro­furan and two tetra­hydro­furan) in the usual envelope conformations and two six-membered rings (tetra­hydro­pyridinone and piperidine) adopting slightly flattened boat and chair conformations, respectively. The dispositions of the carboxyl­ate substituents relative to each other are determined by both steric reasons and inter­molecular C—H⋯O hydrogen bonding and attractive anti­parallel C=O⋯C=O inter­actions [C⋯O = 2.995 (2) Å]

Methyl 4,5-diacet­oxy-1-oxo-2-phenyl­perhydro-4,6-epoxy­cyclo­penta­[c]pyridine-7-carboxyl­ate ethanol solvate

The title compound, the product of an acid-catalysed Wagner–Meerwein skeletal rearrangement, crystallizes as an ethanol monosolvate, C20H21NO8·C2H6O. The title mol­ecule comprises a fused tricyclic system containing two five-membered rings (cyclo­pentane and tetra­hydro­furan) in the usual envelope conformations and one six-membered ring (piperidinone) adopting a flattened twist–boat conformation

Synthesis, X-ray characterization and theoretical study of 3 a ,6:7,9 a-diepoxybenzo [de] isoquinoline derivatives: on the importance of F⋯O interactions

The synthesis, X-ray characterization and Hirshfeld surface analysis of a series of tetrahydrodiepoxybenzo[de]isoquinoline derivatives obtained by the tandem [4+2] cycloaddition between perfluorobut-2-yne dienophile (F3C–C≡C–CF3) and a row of N,N-bis(furan-2-ylmethyl)-4-Rbenzenesulfonamides (bis-dienes, R = Me, F, Cl, Br, I) are reported in this manuscript. The implementation of kinetic/thermodynamic control allowed to obtain both “pincer”- and “domino”-types adducts in good/moderate yields. In the solid state, most of the pincer adducts form self-assembled dimers (R = Me, Cl, Br, I) and, contrariwise, the domino adducts form 1D supramolecular chains, which are described in detail herein. Remarkably, in the self-assembled dimers, bifurcated halogen bonds involving one fluorine atom of the CF3 group and both O-atoms of sulfonamide are formed, which have been analyzed using DFT calculations, QTAIM and NCIplot computational tools.Fil: Grudova, Mariya V.. Peoples’ Friendship University; RusiaFil: Gil, Diego Mauricio. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Khrustalev, Victor N.. Peoples’ Friendship University; Rusia. Institute of Organic Chemistry ND. Zelinsky; RusiaFil: Nikitina, Eugeniya V.. Peoples’ Friendship University; RusiaFil: Sinelshchikova, Anna A.. Academy of Sciences. Frumkin Institute of Physical Chemistry and Electrochemistry; RusiaFil: Grigoriev, Mikhail S.. Academy of Sciences. Frumkin Institute of Physical Chemistry and Electrochemistry; RusiaFil: Kletskov, Alexey V.. Peoples’ Friendship University; RusiaFil: Frontera, Antonio. Universidad de las Islas Baleares; EspañaFil: Zubkov, Fedor I.. Peoples’ Friendship University; Rusi

Methyl (9aR*,10S*,11R*,13aS*,13bS*)-9-oxo-6,7,9,9a,10,11-hexa­hydro-5H,13bH-11,13a-ep­oxy­pyrrolo­[2′,1′:3,4][1,4]diazepino[2,1-a]isoindole-10-carboxyl­ate

The title compound, C17H18N2O4, is the methyl ester of the adduct of intra­molecular Diels–Alder reaction between maleic anhydride and 1-(2-fur­yl)-2,3,4,5-tetra­hydro-1H-pyrrolo­[1,2-a][1,4]diazepine. The mol­ecule comprises a fused penta­cyclic system containing four five-membered rings (viz. pyrrole, 2-pyrrolidinone, tetra­hydro­furan and dihydro­furan) and one seven-membered ring (1,4-diazepane). The pyrrole ring is approximately planar (r.m.s. deviation = 0.003 Å) while the 2-pyrrolidinone, tetra­hydro­furan and dihydro­furan five-membered rings have the usual envelope conformations. The central seven-membered diazepane ring adopts a boat conformation. In the crystal, mol­ecules are bound by weak inter­molecular C—H⋯O hydrogen-bonding inter­actions into zigzag chains propagating in [010]. In the crystal packing, the chains are stacked along the a axis

Methyl 7,8-diacet­oxy-11-oxo-5-(2-oxo­pyrrolidin-1-yl)-7,9-epoxy­cyclo­penta­[4,5]pyrido[1,2-a]quinoline-10-carboxyl­ate sesquihydrate

The title compound, C26H28N2O9·1.5H2O, the product of an acid-catalysed Wagner–Meerwein skeletal rearrangement, crystallizes as a sesquihydrate with the O atom of one of the two independent water mol­ecules occupying a special position on a twofold axis. The organic mol­ecule comprises a fused penta­cyclic system containing two five-membered rings (cyclo­pentane and tetra­hydro­furan) and three six-membered rings (piperidinone, tetra­hydro­pyridine and benzene). The five-membered rings have the usual envelope conformations, and the central six-membered piperidinone and tetra­hydro­pyridine rings adopt boat and sofa conformations, respectively. In the crystal, there are three independent O—H⋯O hydrogen bonds, which link the organic mol­ecules and water mol­ecules into complex two-tier layers parallel to (001). The layers are further linked into a three-dimensional framework by attractive inter­molecular carbon­yl–carbonyl inter­actions

rac-Methyl (3aR*,4S*,5R*,7aR*)-5,7a-bis(acetyloxy)-3-oxo-2-phenyloctahydro-1H-isoindole-4-carboxylate

The title molecule, C20H23NO7, the product of nucleophilic cleavage of the 3a,6-epoxy bridge in 1-oxo-2-phenyloctahydro-3a,6-epoxyisoindole-7-carboxylate, comprises a cis-fused bicyclic system containing a 2-pyrrolidinone ring in an envelope conformation (with the C atom bearing the carboxylate substituent as the flap) and a cyclohexane ring in a chair conformation. The carboxylate substituent occupies the equatorial position, whereas the two acetyloxy substituents are in axial positions. The N atom has a trigonal-planar geometry, the sum of the bond angles being 359.3 (3)°. The dihedral angle between the mean plane of the four planar atoms of the pyrrolidinone ring and the phenyl ring is 25.98 (6)°. In the crystal, molecules are linked into zigzag chains along the c-axis direction by C—H...O hydrogen bonds

Hoveyda–Grubbs catalysts with an N→Ru coordinate bond in a six-membered ring. Synthesis of stable, industrially scalable, highly efficient ruthenium metathesis catalysts and 2-vinylbenzylamine ligands as their precursors

A novel and efficient approach to the synthesis of 2-vinylbenzylamines is reported. This involves obtaining 2-vinylbenzylamine ligands from tetrahydroisoquinoline by alkylation and reduction followed by the Hofmann cleavage. The resultant 2-vinylbenzylamines allowed us to obtain new Hoveyda–Grubbs catalysts, which were thoroughly characterised by NMR, ESIMS, and X-ray crystallography. The utility of this chemistry is further demonstrated by the tests of the novel catalysts (up to 10−2 mol %) in different metathesis reactions such as cross metathesis (CM), ring-closing metathesis (RCM) and ring-opening cross metathesis (ROCM)

Crystal structure of methyl (3RS,4SR,4aRS,11aRS,11bSR)-5-oxo-3,4,4a,5,7,8,9,10,11,11a-decahydro-3,11b-epoxyazepino[2,1-a]isoindole-4-carboxylate

The title compound, C15H19NO4, is the a product of the esterification of the corresponding carbonic acid with methanol. The molecule comprises a fused tetracyclic system containing three five-membered rings (2-pyrrolidinone, tetrahydrofuran and dihydrofuran) and one seven-membered ring (azepane). The five-membered rings have the usual envelope conformations, with the quaternary C atom being the flap atom for the 2-pyrrolidinone ring, and the ether O atom being the common flap atom for the remaining rings. The seven-membered azepane ring adopts a chair conformation with the methine and middle methylene C atoms lying above and below the mean plane defined by the remaining five atoms. The carboxylate substituent is rotated by 77.56 (5)° with respect to the base plane of the tetrahydrofuran ring. In the crystal, the molecules are bound by weak C—H...O hydrogen-bonding interactions into puckered layers parallel to (001)

Crystal structure and Hirshfeld surface analysis of diethyl (3aS,3a1R,4S,5S,6R,6aS,7R,9aS)-3a1,5,6,6a-tetrahydro-1H,3H,4H,7H-3a,6:7,9a-diepoxybenzo[de]isochromene-4,5-dicarboxylate

In the title compound, C18H22O7, two hexane rings and an oxane ring are fused together. The two hexane rings tend toward a distorted boat conformation, while the tetrahydrofuran and dihydrofuran rings adopt envelope conformations. The oxane ring is puckered. The crystal structure features C—H...O hydrogen bonds, which link the molecules into a three-dimensional network. According to a Hirshfeld surface study, H...H (60.3%) and O...H/H...O (35.3%) interactions are the most significant contributors to the crystal packing