α-Carbonyl-N,N-disubstitued formamides (5a~5f) were synthesized from compounds 2a~2f under the condition of pH=8~9. Furthermore, compounds 2α-2f and compounds 3a~3f reacted with trimethyl phosphite in xylene to afford tetrasubstituted vinylphosphonates 6a~6f, 7a~7f, 8a~8f and thiophene derivatives 9a~9f, respectively.
Thiophene derivatives substituted at a position are used in synthesis of pharmaceuticals, pesticides, dyestuffs, chemical reagents and auxilia- ries for high polymers. The important derivatives include thiophene-α- acetic acid, α-chloromethylthiophene, α-acetylthiophene and thiophene- α-formaldehyde. Thiophene-α-acetic acid has a largest consumption a- mount in thiophene derivaties with a margin of about 1000t/a.
However,with the increase of the number of the branched chain on the thiophene ring,the di-and tri-alkylation capability of thiophene derivatives decreased a lot because of the thermodynamics and steric effects,and their primary products are restricted to the mono-alkylated products.
Geometric structures of α-substituted thiophen derivatives were optimized with B3LYP method at 6-31G~* level. Their frontier molecular orbital energy levels and electronic spectra were obtained with TD-DFT method.
Degradation of thiophene-2-carboxylate, furan-2-carboxylate, pyrrole-2-carboxylate and other thiophene derivatives by the bacter
A bacterium of the genus Vibrio, capable of degrading thiophene derivatives, was isolated from enrichment cultures inoculated with oil-contaminated estuarine mud.
Of the thiophene derivatives tested, only thiophene-2-carboxylate (T2C), thiophene-2-acetate and thiophene-2-carbonyl chloride supported growth, but a total of seven were significantly oxidised by resting cells.
The fungus metabolized a series of sulfur compounds - 25 structurally related thiophene derivatives - via several different pathways.
Comparative study of the electrochemical response of poly (alkyl thiophene) derivatives deposited on platinum and titanium elect
The transformation of the 2-amino-5-phenylazo-thiophene derivative9 by potassium hydroxide yields the substituted 3-mercapto-pyridazin-6(1H)one10, with sodium ethoxide the 5-phenylhydrazono-2-oxo-thiolen-3-carbonitrile11 is formed.
In the course of an attempted elimination reaction starting from an isothiochromane derivative substituted with an amino-alcohol moiety, a benzo[c]thiophene derivative formed via a rearrangement reaction was isolated unexpectedly.
Alpha-terthienyl, a phototoxic thiophene derivative from species in the Asteraceae reduced feeding and growth of the phytophagous lepidopteran,Euxoa messoria, when incorporated into artificial diets at a concentration of 100 ppm.
For a thiophene derivative the latter direction of the reaction is observed to a substantially smaller degree.
Vibrational spectra and structure of thiophene derivative sulfones