Search results for "Derivative"
showing 10 items of 1074 documents
A calixarene-based chromoionophore for the larger alkali metals
1995
Abstract A bis(arylazo)calix[5]arene crown ether derivative displays large spectral changes upon complexation of cesium and rubidium salts, with good selectivity over the smaller alkali metals.
ChemInform Abstract: Oxidative Cyclization of Some Aldehyde Semicarbazones Induced by Metallic Salts.
2010
The oxidative cyclization of some aldehyde semicarbazones 10 with four different oxidizing agents has been effected. The structure of the semicarbazones and the nature of cyclizing agent affected the rate and yield of cyclization but they did not show any influence on the regiochemistry of reaction. In fact, 1,2,4-triazoline 20 was the only heterocyclic ring obtained by the cyclization reaction.
Reactions of Piperazin-2-one, Morpholin-3-one, and Thiomorpholin-3-one with Triethyl Phosphite Prompted by Phosphoryl Chloride: Scope and Limitations
2019
The reaction of the title lactams with triethyl phosphite prompted by phosphoryl chloride provided six-membered ring heterocyclic phosphonates or bisphosphonates. These novel scaffolds might be of interest as building blocks in medicinal chemistry. The course of the reaction was dependent on the structure of the used substrate. Thus, morpholin-3-one and thiomorpholin-3-one readily provided the corresponding 1,1-bisphosphonates (compounds 1, 2, 7, 14 and 16), whereas the protection of their nitrogen atom resulted in the formation of dehydrophosphonates (compounds 5, 6, and 8). Piperazin-2-one reacted differently yielding mixture of cis- and trans- piperazine-2,3-diyl-bisphosphonates (compoun…
Plant-growth-regulatingN-(phosphonoacetyl)amines
1994
A series of N‐(phosphonacetyl)amine derivatives were synthesized and screened for plant‐growth regulating activity on Lepidium sativum L. and Cucumis sativus L. Aromatic N‐(phosphonoacetyl)amines. which may be considered as possible analogues of N‐acylaniline herbicides obtained by replacement of their acyl group by the phosphonacetyl moiety, exhibited significant or moderate herbicidal activity. In contrast, N‐(phosphonoacetyl)amino acids and N‐(phosphonoacetyl)aminophosphonic acids promoted the growth of L. sativum and C. sativus roots.
One-Pot Three-Component Solvent-Free Syntheses of n-Alkyl-Bridged N,N,N,N-tetra(2-hydroxybenzyl)diamines and N,N-bis(2-hydroxybenzyl) amines
2010
A simple solvent-free method to prepare four N,N,N’,N’-tetra(2-hydroxy-3,5dimethylbenzyl)diaminoalkanes and four N,N,N’,N’-tetra(2-hydroxy-5-t-butyl-3-methylbenzyl)-diaminoalkanes containing a long n-alkyl-bridge (58 CH2 groups between N-atoms) is described. In addition, preparations of four dihydrochlorides of prepared n-alkyl-bridged N,N,N’,N’-tetra(2-hydroxybenzyl)diamines are described. This method was also tested in the preparation of eight previously reported N,N-bis(2-hydroxybenzyl)amine derivatives.
Studien zum Vorgang der Wasserstoffübertragung, 53. Beitrag zur Kenntnis der elektroreduktiven Spaltung von Hydroxylaminderivaten
1978
Die Elektroreduktion von 26 Hydroxylaminderivaten wird polarographisch und an 6 Beispielen praparativ untersucht. Es wurde gefunden: 1) Dreifach mit Alkyl- oder Arylgruppen substituierte Hydroxylaminderivate werden bis zu einem Potential von -2.5 V (gegen Ag/AgCl/KClges.) nicht elektroreduziert. — 2) Der Einbau von Acylgruppen erleichtert in Abhangigkeit von Art, Zahl und Verknupfungsstelle die Elektroreduktion. Acylreste mit aromatischen Gruppen verschieben das Halbstufenpotential starker nach positiven Werten als aliphatisch substituierte Acylreste (entsprechend: Phthaloyl > Benzoyl > Formyl > Acetyl > Ethoxycarbonyl). Acylgruppen am Sauerstoff des Hydroxylamins fordern die Elektroredukti…
Synthesis and Structural Characterization of a Cyclen-Derived Molecular Cage
2015
Reaction of a tetrafunctionalized cyclen derivative containing four aldehyde groups with an appropriate diamine followed by reduction and demetalation highly efficiently affords a bis(cyclen)-derived molecular cage. Potentiometric investigations show that this compound forms dimetallic complexes with copper(II), with the two metal ions selectively coordinated to the cyclen units. X-ray crystallography indicates that these complexes could give rise to new cascade complexes after incorporation of anions between the metal centers.
Synthesis and electrode reactions of difluorogermanium(IV) porphyrins. Molecular stereochemistry and crystal structure of difluoro-(2,3,7,8,12,13,17,…
1988
The difluorogermanium(IV) porphyrins [GeF2(P)][P = 2,3,7,8,12,13,17,18-octaethylporphyrinate(2–)(oep), 5,10,15,20-tetraphenylporphyrinate(2–)(tpp), or 5,10,15,20-tetra-p-tolylporphyrinate(2–)(tptp)] have been prepared by reacting hydrogen fluoride with the appropriate dichloro derivative [GeCl2(P)]. The complexes were characterized by elemental analysis, 1H n.m.r., i.r., and u.v.–visible spectroscopy. The electrochemical behaviour was investigated in non-aqueous media while spectroelectrochemistry and e.s.r. were used to characterize the oxidized and reduced complexes. Each complex could be reversibly oxidized or reduced by one electron. In each case these electron additions or abstractions…
Organocyanide coordination chemistry: Syntheses, structural characterisations and magnetic properties of copper (II) complexes with a di-imine/pyridi…
2005
Abstract The reactions between the copper (II) salts [CuXL]PF6 (L: 2,6-[1-(2,6-diisopropylphenylimino)ethyl]pyridine) (X = Cl 1, X = Br 2) and LiTCNQ, in a DMF/water mixture, or Et3NH(TCNQ)2, in acetone, produced the new complexes [CuXL(TCNQ)] (X = Cl 3, X = Br 4). For both compounds, crystallographic studies have clearly evidenced the existence of dimeric complexes [{CuClL}(TCNQ)]2 owing to π–π overlap between two adjacent TCNQ − radical anions. Compound 1 reacted with Et4N(C10N7) to afford the mononuclear derivative [CuClL(C10N7)] (5), while its reaction with K2C10N6 produced the dinuclear complex [(CuClL)2(C10N6)] (6). The crystal structures of complexes 5 and 6 have been determined by X…
NonclassicalPschorr andSandmeyer Reactions in Pyrazole Series
2005
The diazonium salt derived from 4-amino-N,1,3-trimethyl-N-(3-methyl-1-phenyl-1H-pyrazol-5-yl)-1H-pyrazole-5-carboxamide (14) was reacted with a mixture of CuSO4 and NaCl, with ascorbic acid as an initiator to afford the planar derivative 4,6-dihydro-1,4,6,8-tetramethyl-3-phenyldipyrazolo[3,4-b:4′,3′-d]pyridin-5(3H)-one (16) and its unexpected isomer 4,6-dihydro-3,4,6,8-tetramethyl-1-phenyldipyrazolo[4,3-b:4′,3′-d]pyridin-5(1H)-one (17), as well as the epimers (3S,4S)- (or (3S,4R)-) and (3S,4R)- (or (3S,4S)-) 4-chloro-2,4-dihydro-1′,3′,5,5′-tetramethyl-2-phenylspiro[pyrazole-3,4′(1′H)-pyrrolo[3,4-c]pyrazol]-6′(5′H)-one (18a and b, respectively). Epimers 18a and b were converted under basic c…