Stabilization of Square Planar Silicon: A New Building Block for Conjugated Si-Containing Systems

2009 ◽  
Vol 113 (4) ◽  
pp. 707-712 ◽  
Author(s):  
D. Szieberth ◽  
M. Takahashi ◽  
Y. Kawazoe
Keyword(s):  
Building Block ◽  
Square Planar ◽  
Planar Silicon

10,15-di(4-pyridyl)-5,20-di(4-tolyl)-21-thiaporphyrin as a building block for porphyrin coordination arrays

2003 ◽  
Vol 07 (01) ◽  
pp. 8-16 ◽  
Author(s):  
Anna Berlicka ◽  
Ewa Pacholska ◽  
Lechosław Latos-Grażyński
Keyword(s):  
Self Assembly ◽  
Building Block ◽  
Chemical Properties ◽  
Bidentate Ligand ◽  
Pyridyl Ring ◽  
Nmr Studies ◽  
H Nmr ◽  
Square Planar ◽  
Phenyl Rings ◽  
Spectroscopic Probe

10,15-di(4-pyridyl)-5,20-di(4-tolyl)-21-thiaporphyrin, ( SDPyDTP ) H , was prepared by condensation of 2,5-bis(4-tolylhydroxymethyl)thiophene, pyrrole and 4-pyridinecarboxaldehyde in boiling propionic acid. The synthesis introduced two pyridyl substituents at two defined (opposite to thiophene) meso positions of the porphyrin periphery. The self-assembly of the angular 10,15-dipyridyl-21-thiaporphyrin modules with cis square-planar diphosphineplatinum(II) complex leads to a cyclic rhomboid dimer [ Pt ( DPPP )( SDPyDTP ) H ]2( OTf )4. The molecule acquires butterfly geometry. The 1 H NMR studies confirmed the π-π stacking of the pyridyl ring with the equatorial phenyl rings of the phosphine fragment. The conformational equilibrium, interchanging the phenyl ring positions and affording the mixture of seven conformers in solution, has been considered. 1 H NMR> spectroscopy was applied to identify oligomeric species, constructed by coordination of ( SDPyDTP ) H to the paramagnetic nickel(II) complex 5,10,15,20-tetra(4-tolyl)-21-thiaporphyrin, ( STTP ) Ni II Cl . ( SDPyDTP ) H acts as a mono- or bidentate ligand coordinating by meso-pyridyl substituents. Using the paramagnetically shifted resonances as an unambiguous spectroscopic probe, 1 H NMR spectroscopy readily discriminated between five- {[( STTP ) Ni II ](( SDPyDTP ) H )} and six-coordinate {[( STTP ) Ni II](( SDPyDTP ) H )2} oligomeric subunits. The applicability of 10,15-di(4-pyridyl)-5,20-di(4-tolyl)-21-thiaporphyrin as a suitable building block in construction of larger molecules was confirmed. The new route to modify the porphyrin coordination arrays, which preserves the overall architecture but modifies intrinsic chemical properties, using heteroporphyrin was demonstrated.

A new P,S-coordinating ferrocenyl ligand: synthesis of a precursor and its coordination compounds with PdII and PtII

2014 ◽  
Vol 70 (5) ◽  
pp. 460-464 ◽  
Author(s):  
Nardjes Mouas Toma ◽  
Jean-Claude Daran ◽  
Hocine Merazig ◽  
Eric Manoury
Keyword(s):  
Building Block ◽  
Planar Geometry ◽  
Dinuclear Complexes ◽  
Enantiomerically Pure ◽  
Metal Atoms ◽  
Square Planar ◽  
Ongoing Development ◽  
Cl Atoms ◽  
Crude Material ◽  
By Products

In our ongoing development of ferrocene ligands, 1-dimethylamino-2-(diphenylphosphinothioyl)ferrocene is being used as a convenient building block to obtain racemic or enantiomerically pure ligands. Using this building block in large excess allowed the formation of several by-products, two of which have already been reported; the structure of a third by-product, namely 1-(diphenylphosphinothioyl)-2-{[(diphenylphosphinothioyl)sulfanyl]methyl}ferrocene, [Fe(C5H5)(C30H25P2S3)], is presented here. The crystal structure is built up from a ferrocene unit, with one of the cyclopentadienyl (Cp) rings substituted in the 1- and 2-positions by a protected diphenylphosphinothioyl group and a [(diphenylphosphinothioyl)sulfanyl]methyl fragment, –CH2SP(=S)Ph2. There are C—H...S interactions which result in the formation of chains parallel to the c axis. After desulfurization, the crude material was then reacted with Pd and Pt (M) precursors [MCl2(CH3CN)2] to yield two isostructural dinuclear complexes arranged around twofold axes, namely (R,R/S,S)-bis{μ-[2-(diphenylphosphanyl)ferrocen-1-yl]methanethiolato-κ3 P,S:S}bis[chloridopalladium(II)] pentane disolvate, [Pd2{Fe(C5H5)(C18H15PS)}2Cl2]·2C5H12, and the platinum(II) analogue, (R,R/S,S)-bis{μ-[2-(diphenylphosphanyl)ferrocen-1-yl]methanethiolato-κ3 P,S:S}bis[chloridoplatinum(II)] toluene monosolvate, [Pt2{Fe(C5H5)(C18H15PS)}2Cl2]·C7H8, in which the two metal atoms present a slightly distorted square-planar geometry formed by two bridging S atoms and P and Cl atoms. The P,S-chelating ligand results from the rupture of one of the P—S bonds in the starting ligand. These dinuclear complexes display a butterfly geometry. Surprisingly, only the (R,R/S,S) diastereoisomer has been isolated.

Crystal chemistry of high-Tc superconductors

1990 ◽  
Vol 48 (4) ◽  
pp. 1118-1119
Author(s):  
Maryvonne Hervieu
Keyword(s):  
Oxygen Deficiency ◽  
Large Family ◽  
Copper Oxides ◽  
High Tc Superconductors ◽  
High Tc ◽  
Single Mechanism ◽  
Square Planar ◽  
History Of ◽  
Bismuth Cuprates ◽  
New Compounds

Four years after the discovery of superconductivity at high temperature in the Ba-La-Cu-O system, more than thirty new compounds have been synthesized, which can be classified in six series of copper oxides: La2CuO4 - type oxides, bismuth cuprates, YBa2Cu3O7 family, thallium cuprates, lead cuprates and Nd2CuO4 - type oxides. Despite their quite different specific natures, close relationships allow their structures to be simply described through a single mechanism. The fifth first families can indeed be described as intergrowths of multiple oxygen deficient perovskite slabs with multiple rock salt-type slabs, according to the representation [ACuO3-x]m [AO]n.The n and m values are integer in the parent structures, n varying from 0 to 3 and m from 1 to 4; every member of this large family can thus be symbolized by [m,n]. The oxygen deficient character of the perovskite slabs involves the existence or the co-existence of several types of copper environment: octahedral, pyramidal and square planar.Both mechanisms, oxygen deficiency and intergrowth, are well known to give rise easily to nonstoichiometry phenomena. Numerous and various phenomena have actually been characterized in these cuprates, strongly depending on the thermal history of the samples.

Microbe Engineering of Guaia-6,10(14)-diene as a Building Block for the Semisynthetic Production of Plant-Derived (−)-Englerin A

2019 ◽  
Author(s):  
Thomas Siemon ◽  
Zhangqian Wang ◽  
Guangkai Bian ◽  
Tobias Seitz ◽  
Ziling Ye ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Saccharomyces Cerevisiae ◽  
Synthetic Biology ◽  
Chemical Synthesis ◽  
Building Block ◽  
Transient Receptor Potential ◽  
Receptor Potential ◽  
Economical Method ◽  
Englerin A ◽  
Transient Receptor

Herein, we report the semisynthetic production of the potent transient receptor potential canonical (TRPC) channel agonist (−)-englerin A (EA), using guaia-6,10(14)-diene as the starting material. Guaia-6,10(14)-diene was systematically engineered in Escherichia coli and Saccharomyces cerevisiae using the CRISPR/Cas9 system and produced with high titers. This provided us the opportunity to execute a concise chemical synthesis of EA and the two related guaianes (−)-oxyphyllol and (+)-orientalol E. The potentially scalable approach combines the advantages of synthetic biology and chemical synthesis and provides an efficient and economical method for producing EA as well as its analogs.

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