Funktionalisierte β‐Hydroxydithiozimtsäurederivate als Liganden. Kristallstrukturanalyse von 4′‐Hydroxy‐β‐hydroxydithiozimtsäuremethylester

Abstract

Aus silylgeschütztem 4′‐Hydroxyacetophenon (1) entsteht durch Umsetzung mit Schwefelkohlenstoff und Iodmethan in Gegenwart von Kalium‐tert‐butylat der silylsubstituierte 4′‐Hydroxy‐β‐hydroxydithiozimtsäuremethylester (2). Die Molekülstruktur des nach Abspaltung der Schutzgruppe entstehenden Esters 3 wurde durch Röntgenstrukturanalyse bestimmt. Die phenolische OH‐Gruppe wird mit DL‐α‐Liponsäure (4) verestert. Der so zugängliche 4′‐(1, 2‐Dithiolan‐3‐pentanoyl)‐β‐hydroxydithiozimtsäuremethylester (5) bildet mit NiII, PdII und PtII Komplexe.

Resonance‐Assisted Hydrogen Bonding as a Driving Force in Synthesis and a Synthon in the Design of Materials

“…He has authored one book,o ver 600 research publications, and 33 patents, edited four books, and presented over 100 invited lectures at internationalc onferences.H is work has received over 14 000 citations (h-index = 56;W eb of Science). [6] The most well-established cases of RAHB( Scheme3)i nclude intramolecular Hbonds in b-diketones (I), [24,[40][41][42] b-enaminones (II), [24,[40][41][42]46] Schiff bases (III), [47][48][49][50] b-enaminoimines (IV), [51][52][53][54] hydrazones (V and VI), [55][56][57] formazans (VII), [58][59][60] 1,3,5-triazapentadienes (VIII), [61][62][63] orthosubstituted aromatic compounds (IX-XII), [64][65][66] oximes (XIII-XVI), [29,[67][68][69] mercaptans (or thiols) (XVII-XIX), [70][71][72] thioketones (XX-XXII), [73][74][75] selenones or tellurones (XXIII and XXIV), [76][77][78][79][80]…”

“…A variety of heteroconjugated RAHB systems was studied with the aim of determining crystal engineering rules for the production of materials with potential practical applications . The most well‐established cases of RAHB (Scheme ) include intramolecular H‐bonds in β‐diketones ( I ), β‐enaminones ( II ), Schiff bases ( III ), β‐enaminoimines ( IV ), hydrazones ( V and VI ), formazans ( VII ), 1,3,5‐triazapentadienes ( VIII ), ortho ‐substituted aromatic compounds ( IX – XII ), oximes ( XIII – XVI ), mercaptans (or thiols) ( XVII – XIX ), thioketones ( XX – XXII ), selenones or tellurones ( XXIII and XXIV ), and 8‐ or 10‐membered RAHB system containing compounds ( XXV and XXVI ) . These RAHB moieties are ubiquitous in various fields, including organic and inorganic synthesis, crystal growth and design, supramolecular chemistry, medicinal chemistry, and materials chemistry, and have been used in the activation of covalent bonds, crystal engineering, dynamic combinatorial chemistry, molecular recognition, E / Z isomeric resolution, racemization/epimerization of amino acids, solvatochromism, and liquid‐crystalline materials, among other applications.…”

Synthesis and analytical characterization of novel pyridyl‐substituted 1,1′‐ethenedithiolato complexes

“…The important 1 H NMR resonance signals are provided by the methine group. According to the literature studies of free substituted β-hydroxydithiocinnamic acids and their esters [7,[9][10][11], the signals of the complexes should be shifted highfield due to their π-backbonding. This effect can be observed at least in the spectra of the 3-and 4-pyridyl substituted complexes 7-18, whose signals are detected between δ = 6.3 and 6.6.…”

“…In the complexes 1-18, the 13 C NMR spectra exhibit a downfield shifted single resonance of the methine carbon atoms within a range of δ = 117-120 with a 3 J C-Pt coupling (59)(60)(61)(62)(63)(64)(65)(66)(67)(68)(69)(70)(71)(72)(73)(74)(75) and a small 4 J C-P coupling . The C O signals appear at about δ = 186.0-193.5 and are shifted downfield in contrast to those in the uncoordinated dithioacids [7, [9][10][11]. Table 3 illustrates the different 13 C NMR signals and the coupling constants of the methine carbon atom.…”

“…The UV-VIS spectra of all the complexes 1-18 show absorption bands in a range of 370-390 nm with values of lg ε at about 4.4. In the palladium (4,5,10,11,16,17) and nickel (6,12,18) complexes another absorption band is found at wavelengths around 330 nm (lg ε at about 4.3). Resulting data of the UV-VIS experiments are summarized in Table 5.…”