Cationic tetrakis(nucleobase)complexes of PtII as metalloligands and potential building blocks for molecular architectures

2005 ◽  
pp. 1679 ◽  
Author(s):  
Pablo J. Sanz Miguel ◽  
Bernhard Lippert
Keyword(s):  
Building Blocks ◽  
Molecular Architectures

Synthesis of Monofunctionalized Calix[5]arenes

Synthesis ◽  
2017 ◽  
Vol 50 (03) ◽  
pp. 676-684 ◽  
Author(s):  
Arne Lützen ◽  
Björn Ingenfeld ◽  
Steffen Straub ◽  
Christopher Frömbgen
Keyword(s):  
Hydrogen Bonds ◽  
Functional Groups ◽  
Functional Group ◽  
Building Blocks ◽  
Cone Conformation ◽  
Oh Groups ◽  
Tert Butyl ◽  
Fragment Condensation ◽  
Molecular Architectures ◽  
Phenolic Oh Groups

Seven OH-free and O-permethylated monofunctionalized calix[5]arenes carrying either additional methyl or tert-butyl groups are prepared following fragment condensation protocols. This strategy proves to be superior to previous approaches. Calix[5]arenes with free OH groups all adopt a cone conformation stabilized by a seam of hydrogen bonds at the lower rim. Post-condensation modifications, i.e., methylation of phenolic OH groups or functional group interconversions can also be achieved. Bulky tert-butyl groups are also found to stabilize the cone conformations of O-methylated compounds. These compounds offer versatile functional groups that make these concave molecules interesting building blocks for the synthesis of more sophisticated molecular architectures.

scholarly journals Efficient synthesis of 4-substituted-ortho-phthalaldehyde analogues: toward the emergence of new building blocks

2019 ◽  
Vol 15 ◽  
pp. 721-726 ◽  
Author(s):  
Clémence Moitessier ◽  
Ahmad Rifai ◽  
Pierre-Edouard Danjou ◽  
Isabelle Mallard ◽  
Francine Cazier-Dennin
Keyword(s):  
Building Blocks ◽  
Efficient Synthesis ◽  
Oxidation Step ◽  
Fluorimetric Analysis ◽  
Molecular Architectures

4-Methoxy-ortho-phthalaldehyde and 4-hydroxy-ortho-phthalaldehyde are potentially useful molecules for fluorimetric analysis of a variety of amines and for the elaboration of complex molecular architectures. Nevertheless, literature generally describes their synthesis in very low yield (below 5%), mainly due to the inefficiency of the last oxidation step. In this paper, we report a reliable synthesis of 4-substituted-ortho-phthalaldehyde analogues in 51% overall yield owing to the addition of a protecting step of the unstable key intermediate 4,5-dihydroisobenzofuran-5-ol. Oxidation and deprotection steps were also studied in order to provide an effective availability of these two dialdehyde compounds that may increase their future applications.

scholarly journals Combinatorial chemistry in nematodes: modular assembly of primary metabolism-derived building blocks

2015 ◽  
Vol 32 (7) ◽  
pp. 994-1006 ◽  
Author(s):  
Stephan H. von Reuss ◽  
Frank C. Schroeder
Keyword(s):  
Combinatorial Chemistry ◽  
Building Blocks ◽  
Nematode Species ◽  
Primary Metabolism ◽  
Modular Assembly ◽  
C Elegans ◽  
Molecular Architectures

Nematodes are amazingly skilled chemists: using simple building blocks from conserved primary metabolism and a strategy of modular assembly, C. elegans and other nematode species create complex molecular architectures to regulate their development and behaviour.

Synthesis and properties of phenyleneethynylene-based dendritic structures

2006 ◽  
Vol 78 (4) ◽  
pp. 847-853 ◽  
Author(s):  
Jean-François Nierengarten
Keyword(s):  
Light Harvesting ◽  
Building Blocks ◽  
Conjugated Systems ◽  
Molecular Architectures ◽  
Dendritic Structures

In this paper, we report on our ongoing progress on the synthesis and study of branched molecular architectures with a conjugated scaffold. Specifically, new conjugated dendrons incorporating 1,2,4-triethynyl-phenyl units have been developed and used as building blocks for the synthesis of isomeric branched conjugated systems and light-harvesting dendrimers.

Tricyanometalate molecular chemistry: A type of versatile building blocks for the construction of cyano-bridged molecular architectures

2011 ◽  
Vol 255 (15-16) ◽  
pp. 1713-1732 ◽  
Author(s):  
Shi Wang ◽  
Xue-Hua Ding ◽  
Jing-Lin Zuo ◽  
Xiao-Zeng You ◽  
Wei Huang
Keyword(s):  
Building Blocks ◽  
Molecular Chemistry ◽  
Molecular Architectures

Photochemical Evolution of Interstellar/Precometary Organic Material

1997 ◽  
Vol 161 ◽  
pp. 23-47 ◽  
Author(s):  
Louis J. Allamandola ◽  
Max P. Bernstein ◽  
Scott A. Sandford
Keyword(s):  
Origin Of Life ◽  
Building Blocks ◽  
Complex Species ◽  
Infrared Observations ◽  
Interstellar Ice ◽  
Polycyclic Aromatic ◽  
Ultraviolet Photolysis ◽  
The Origin Of Life ◽  
Simple Molecules ◽  
Complex Organic

AbstractInfrared observations, combined with realistic laboratory simulations, have revolutionized our understanding of interstellar ice and dust, the building blocks of comets. Since comets are thought to be a major source of the volatiles on the primative earth, their organic inventory is of central importance to questions concerning the origin of life. Ices in molecular clouds contain the very simple molecules H2O, CH3OH, CO, CO2, CH4, H2, and probably some NH3and H2CO, as well as more complex species including nitriles, ketones, and esters. The evidence for these, as well as carbonrich materials such as polycyclic aromatic hydrocarbons (PAHs), microdiamonds, and amorphous carbon is briefly reviewed. This is followed by a detailed summary of interstellar/precometary ice photochemical evolution based on laboratory studies of realistic polar ice analogs. Ultraviolet photolysis of these ices produces H2, H2CO, CO2, CO, CH4, HCO, and the moderately complex organic molecules: CH3CH2OH (ethanol), HC(= O)NH2(formamide), CH3C(= O)NH2(acetamide), R-CN (nitriles), and hexamethylenetetramine (HMT, C6H12N4), as well as more complex species including polyoxymethylene and related species (POMs), amides, and ketones. The ready formation of these organic species from simple starting mixtures, the ice chemistry that ensues when these ices are mildly warmed, plus the observation that the more complex refractory photoproducts show lipid-like behavior and readily self organize into droplets upon exposure to liquid water suggest that comets may have played an important role in the origin of life.

Laboratory and in-situ analysis of comet dust

1988 ◽  
Vol 46 ◽  
pp. 8-9
Author(s):  
D.E. Brownlee ◽  
A.L. Albee
Keyword(s):  
Electron Microscopy ◽  
Solar System ◽  
Laboratory Study ◽  
Isotopic Analysis ◽  
Building Blocks ◽  
Sem Analysis ◽  
Early Solar System ◽  
Cometary Material ◽  
Comet Dust

Comets are primitive, kilometer-sized bodies that formed in the outer regions of the solar system. Composed of ice and dust, comets are generally believed to be relic building blocks of the outer solar system that have been preserved at cryogenic temperatures since the formation of the Sun and planets. The analysis of cometary material is particularly important because the properties of cometary material provide direct information on the processes and environments that formed and influenced solid matter both in the early solar system and in the interstellar environments that preceded it.The first direct analyses of proven comet dust were made during the Soviet and European spacecraft encounters with Comet Halley in 1986. These missions carried time-of-flight mass spectrometers that measured mass spectra of individual micron and smaller particles. The Halley measurements were semi-quantitative but they showed that comet dust is a complex fine-grained mixture of silicates and organic material. A full understanding of comet dust will require detailed morphological, mineralogical, elemental and isotopic analysis at the finest possible scale. Electron microscopy and related microbeam techniques will play key roles in the analysis. The present and future of electron microscopy of comet samples involves laboratory study of micrometeorites collected in the stratosphere, in-situ SEM analysis of particles collected at a comet and laboratory study of samples collected from a comet and returned to the Earth for detailed study.

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