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Synthesis of α,β'- and β,β'-linked dimethoxycarbonyldipyrromethanes by Rothemund-type condensation

2012-7-15, Journot, Guillaume, Stoeckli-Evans, Helen, Neier, Reinhard

The Rothemund-type condensation of methoxycarbonylpyrrole with acetone produces mainly the α,β'-linked dipyrromethane, a building block for the synthesis of N-confused macrocycles. The influence of the reaction conditions on the regioselectivity of the process is reported. The x-ray structures of the α,α'-, α,β'- and β,β'-linked dipyrromethanes show an interesting discrimination of the structurally different types of hydrogen bonds. [on SciFinder(R)]

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4-Chloro-benzoyl-meso-octa-methyl-calix[2]pyrrolidino[2]pyrrole: an acyl chloride derivative of a partially reduced calix[4] pyrrole

2012, Journot, Guillaume, Neier, Reinhard, Stoeckli-Evans, Helen

In the title compound, C(35)H(47)ClN(4)O, the two pyrrolidine rings have envelope conformations. The conformation of the macrocycle is stabilized by N-H(midline ellipsis)N hydrogen bonds and a C-H(midline ellipsis)N inter-action. The benzoyl ring is inclined to the adjacent pyrrole ring by 11.66 (11)°, with a centroid-centroid distance of 3.7488 (13) Å. In the crystal, molecules are linked by N-H(midline ellipsis)O hydrogen bonds into helical chains propagating in [010] and C-H(midline ellipsis)O and C-H(midline ellipsis)? interactions are also observed.

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2,2'-[(2S*,6R*)-Piperidine-2,6-di-yl]-di-pro-pan-2-ol

2012, Journot, Guillaume, Neier, Reinhard, Stoeckli-Evans, Helen

In the title compound, C(11)H(23)NO(2), the piperidine ring has a chair conformation. The two hy-droxy H atoms are disordered over two positions with fixed occupancy ratios of 0.57:0.43 and 0.63:0.37. In the mol-ecule, there are two short N-H(midline ellipsis)O inter-actions. In the crystal, four symmetry-related mol-ecules are linked by O-H(midline ellipsis)O hydrogen bonds to form a cage-like arrangement, centered about the point of inter-section of three twofold axes. These cages stack along the [100] direction.

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2,2'-[(2S*,6R*)-Piperidine-2,6-diyl]dipropan-2-ol

2012, Journot, Guillaume, Neier, Reinhard, Stoeckli-Evans, Helen

In the title compd., C11H23NO2, the piperidine ring has a chair conformation. The two hydroxy H atoms are disordered over two positions with fixed occupancy ratios of 0.57:0.43 and 0.63:0.37. In the mol., there are two short N-H···O interactions. In the crystal, four symmetry-related mols. are linked by O-H···O H bonds to form a cage-like arrangement, centered about the point of intersection of three 2-fold axes. These cages stack along the [100] direction. Crystallog. data and at. coordinates are given. [on SciFinder(R)]

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4-Chlorobenzoyl-meso-octamethylcalix[2]pyrrolidino[2]pyrrole: an acyl chloride derivative of a partially reduced calix[4] pyrrole

2012, Journot, Guillaume, Neier, Reinhard, Stoeckli-Evans, Helen

In the title compd., C35H47ClN4O, the two pyrrolidine rings have envelope conformations. The conformation of the macrocycle is stabilized by N-H···N H bonds and a C-H···N interaction. The benzoyl ring is inclined to the adjacent pyrrole ring by 11.66(11)°, with a centroid-centroid distance of 3.7488(13) Å. In the crystal, mols. are linked by N-H···O H bonds into helical chains propagating in [010] and C-H···O and C-H···? interactions are also obsd. [on SciFinder(R)]

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The hydrogenation of heterocyclic calix[4]arenes, a transformation leading to novel macrocyclic ligands

2012, Journot, Guillaume, Jones, Christopher R., Blangy, Valeria, Neier, Reinhard

A review. Hydrogenation reactions of calix[4]furan and calix[4]pyrrole were reviewed together with the authors' own work in this field. A short description of the metal binding process of our new calix[4]pyrrolidines (= the fully satd. calix[4]pyrrole) with Cu was discussed as a typical example of the metal binding capacities. The new calix[4]pyrrolidines can be structurally classified as new stiffened macrocyclic crown ethers or as satd. analogs of the porphyrin-derived "pigments of life". [on SciFinder(R)]

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2-[2-(Pyrrolidin-2-yl)propan-2-yl]-1H-pyrrole and its amide derivative 1-{2-[2-(1H-pyrrol-2-yl)propan-2-yl]pyrrolidin-1-yl}ethanone

2012, Journot, Guillaume, Neier, Reinhard, Stoeckli-Evans, Helen

In the title compds., C11H18N2, (II), and C13H20N2O, (III), the pyrrolidine rings have twist conformations. Compd. (II) crystallizes with two independent mols. (A and B) in the asym. unit. The mean planes of the pyrrole and pyrrolidine rings are inclined to one another by 89.99 (11) and 89.35 (10)° in mols. A and B, resp. In (III), the amide deriv. of (II), the same dihedral angle is much smaller, at only 13.42 (10)°. In the crystal structure of (II), the individual mols. are linked via N-H···N hydrogen bonds to form inversion dimers, each with an R22(12) graph-set motif. In the crystal structure of (III), the mols. are linked via N-H···O hydrogen bonds to form inversion dimers with an R22(16) graph-set motif. [on SciFinder(R)]

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4-Methoxybenzoyl-meso-octamethylcalix[2]pyrrolidino[2]pyrrole: an acyl chloride derivative of a partially reduced calix[4]pyrrole

2012, Journot, Guillaume, Neier, Reinhard, Stoeckli-Evans, Helen

In the title compd., C36H50N4O2, the two pyrrolidine rings have envelope conformations. The conformation of the macrocycle is stabilized by N-H···N H bonds and a C-H···N interaction. The benzoyl ring is inclined to an adjacent pyrrole ring by 6.76(9)°, with a centroid-to-centroid distance of 3.6285(10) Å. In the crystal, apart from a C-H···O and a C-H···? interaction, mols. are linked via an N-H···O H bond, giving helical chains propagating along [010]. Crystallog. data and at. coordinates are given. [on SciFinder(R)]

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4-Meth-oxy-benzoyl-meso-octa-methyl-calix[2]pyrrolidino[2]pyrrole: an acyl chloride derivative of a partially reduced calix[4]pyrrole

2012, Journot, Guillaume, Neier, Reinhard, Stoeckli-Evans, Helen

In the title compound, C(36)H(50)N(4)O(2), the two pyrrolidine rings have envelope conformations. The conformation of the macrocycle is stabilized by N-H(midline ellipsis)N hydrogen bonds and a C-H(midline ellipsis)N inter-action. The benzoyl ring is inclined to an adjacent pyrrole ring by 6.76 (9)°, with a centroid-to-centroid distance of 3.6285 (10) Å. In the crystal, apart from a C-H(midline ellipsis)O and a C-H(midline ellipsis)? inter-action, mol-ecules are linked via an N-H(midline ellipsis)O hydrogen bond, leading to the formation of helical chains propagating along [010].

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Synthesis of Calix[4]pyrrolidine, Calix[m]tetrahydrofuran[n]pyrrolidine (m+n=4) and similar macrocyclic systems - elucidation of the hydrogenation sequence and factors influencing the stereoselectivity

2012, Journot, Guillaume, Neier, Reinhard

The first meso-octaalkylporphyrinogen (calix[4]pyrrole) was synthesized by Baeyer more than 120 years ago, mixing pyrrole and acetone in the presence of an acid. We have performed a thorough study of the catalytic hydrogenation of calix[4]pyrrole 1, by using common as well as novel heterogeneous catalysts based on transition metals (Pd, Rh, Ru) supported on solid matrices. Another investigation concerning the hydrogenation reaction was performed using twelve different macrocyclic substrates. Different factors were tested, which might influence the stereoselectivity during the hydrogenation process and therefore the number of diastereomers obtained. One of the macrocycles synthesized, offers interesting perspectives for the development of novel catalysts. In this context, we investigated the reactivity and the modification of this macrocycle. A thorough study of the nucleophilic properties and a kinetic study allow the discovery the factors that influence the reactivity of these macrocycles.