Synthesis of a novel benzoxazine containing benzoxazole structure

<正>A high-purity benzoxazine(Boz-BOA) containing benzoxazole structure was successfully synthesized by three-step synthetic method using 2-(4-aminophenyl)-1H-benzoxazole-5-amine(BOA) and ortho-hydroxybenzaldehyde.The structure of Boz-BOA was confirmed by FTIR and ~1H NMR spectra.The DSC was utilized to probe the curing behavior of Boz-BOA and exhibited a narrow melting peak and curing exothermic peak.     

Synthesis and structure of heterometallic complexes (RhFe, CoFe) containing bridging 1,2-dicarba-closo-dodecarborane-1,2-dichalcogenolato ligands

The prototype hetero-binuclear complexes containing metal-metal bonds, {CpRh[E2C2(B10H10)]}[Fe(CO)3] (Cp = Cp* = eta 5-Me5C5, E = S(5a), Se(5b); Cp = Cp = eta 5-1,3-tBu2C5H3, E = S(6a), Se(6b)) and {CpCo[E2C2(B10H10)]}[Fe(CO)3] (Cp = Cp* = eta 5-Me5C5, E = S(7a), Se(7b); Cp = Cp = eta 5-C5H5, E = S(8a), Se(8b)) were obtained from the reactions of 16-electron complexes CpRh[E2C2(B10H10)] (Cp = Cp*, E = S(1a), Se(1b); Cp = Cp, E = S(2a), Se(2b)), CpCo[E2C2(B10H10)] (Cp = Cp*, E = S(3a), Se(3b); Cp = Cp, E = S(4a), Se(4b)) with Fe(CO)5 in the presence of Me3NO. The molecular structures of {Cp*Rh[E2C2(B10H10)]}[Fe(CO)3] (E = S(5a), Se(5b)), {CpRh[S2C2(B10H10)]}[Fe(CO)3] (6a) {Cp*Co[S2C2(B10H10)]}[Fe(CO)3] (7a) and {CpCo[S2C2(B10H10)]}[Fe(CO)3] (8a) have been determined by X-ray crystallography. All these complexes were characterized by elemental analysis and IR and NMR spectra.     

A novel one-pot, three-component reaction: formation of tricyclic 1,2-dihydropyridines via mesomeric betaines

A one-pot, three-component reaction of pyridine, thiophthalimide and acyl chloride gives novel tricyclic 1,2-dihydropyridines regio- and stereoselectively, in which a mesomeric betaine would be a key intermediate for [4+2]-cycloaddition reaction with thiocarbonyl compounds.     

Synthesis and structure of 1,2-diphosphacyclopentenes

Treatment of titanacyclobutenes with two equivalents of dichlorophenylphosphine affords diphosphacyclopentenes, two examples of which were structurally characterized by single-crystal X-ray diffraction analysis. The analogous reaction of a titanacyclobutene with dichlorophenylstibine affords the corresponding distibacyclopentene as well as a stibacyclobutene. © 1996 John Wiley & Sons, Inc.     

Synthesis and structure of novel phosphonodipeptides containing a uracil or thymine group

A series of novel phosphonodipeptides containing a uracil or thymine group was synthesized in 54.2–74.1% yields by means of a peptide coupling reaction with DCC as the dehydrating agent and 1‐hydroxybezotriazole as the activating agent of the carboxyl group. All products were characterized by ¹H NMR, ³¹P NMR and IR spectra, and by elemental analyses. The crystal and molecular structure of compound 6c has been determined by X‐ray diffraction. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:422–427, 2000     

Synthesis, structure and insecticidal activity of some novel amides containing N-pyridylpyrazole

A novel series of amides containing N-pyridylpyrazole were designed and synthesized. All of the compounds were characterized and confirmed by IR, ¹H NMR, ¹³C NMR, MS and elemental analysis. The single crystal structure of 9d was determined by X-ray diffraction. The bioassay tests showed that the title compounds exhibited good insecticidal activities against Mythimna separata Walker, diamondback moth and Laphygma exigua Hübner.     

Synthesis of highly symmetric mesomeric triazaphenalene betaines

The synthesis of seven mesomeric triazaphenalene betaines 4a‐g by condensation reaction of hexahydro‐2H‐pyrimido[1,2‐a]pyrimidine 1 with diethyl malonates 2a‐g or with bis(2,4,6‐trichlorophenyl)malonates 3c,f has been achieved. The guanidine 1 forms in benzene solution a salt with trimethyl methanetricarboxylate 5 which upon heating produces 4a.     

Synthesis of 1,2-azaphospholanes containing an amino acid fragment

2-Oxo-1,2-azaphospholanes and 1,2-azaphospholanium salts containing an amino acid fragment were synthesized by intramolecular P-alkylation of N-3-chloropropyl-substituted tricoordinate phosphorus amides. Hydrolysis of 2-oxo-1,2-azaphospholanes at the P-N bond gives rise to γ-aminopropylphosphonic acid derivatives. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2557–2562, November, 2005.     

Synthesis of novel acyclonucleosides containing pyridazine

This paper presents the synthesis of some novel acyclonucleosides involving pyrrolo[2,3‐c]pyridazine and 4‐hydroxybutyl side chain.     

Synthesis,crystal structure and magnetic property of a novel ion‐pair nickel(III) complex containing 1,2‐benzenedithiolate

A new ion‐pair complex [1‐(4‐nitrobenzyl)pyridinium][Ni(bdt)₂] (1), in which bdt^2? = 1,2‐benzenedithiolate, has been synthesized and characterized. The X‐ray structure analysis shows that the anions are centrosymmetric, the two non‐equivalent anions form different uniform‐spaced stacking pattern and the weak H‐bonding interactions of C? H…S were observed in 1. The temperature dependence of magnetic susceptibilities of 1 indicates ferromagnetic behavior in the antiferromagnetic exchange system, which may arise from spin‐canting. Copyright © 2007 John Wiley & Sons, Ltd.     

Pseudo-cross-conjugated mesomeric betaines. 1. Synthesis of pseudo-cross-conjugated mesomeric betaines from quinoxaline derivatives

A new method for the synthesis of pseudo-cross-conjugated mesomeric betainic heterocyclic compounds with an angular nitrogen atom has been developed consisting in the reaction of 1,4-dielectrophile — -carbethoxy-2-(3-chloro)quinoxalylacetonitrile with azoles. Experimental regularities have been studied and a reaction mechanism has been proposed including the stage of formation of an ylide from a quaternary azolium salt. A pseudo-crossconjugated mesomeric betainic heterocyclic compound containing a thiazole ring compound has been synthesized for the first time.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1528–1533, November, 1992.     

Synthesis of novel texaphyrins containing lanthanides and boron

Texaphyrin macrocycles that contain gadolinium or lutetium, such as motexafin gadolinium and motexafin lutetium, are versatile anticancer therapeutics and diagnostics. Gadolinium texaphyrins substituted with carborane clusters could also find application in combined gadolinium and boron neutron capture therapy (GdB-NCT). The synthesis and characterization of novel texaphyrins containing gadolinium or lutetium in the pentaaza core and two carborane clusters bound to opposite pyrrol units of the macrocycle are described.     

Synthesis and structure of novel organocycloborates

A series of alpha,omega-boryl(bromo)alkanes of the general formula R2B-(CH2)n-Br (n = 3, 4, 5, 6) was obtained in high yield following a standard hydroboration protocol. Upon treatment with Mg turnings and formation of the respective Grignard species, all alkanes with n = 4 to 6 underwent an unprecedented boron-centered cyclisation reaction with formation of boratacyclopentanes, -hexanes, and -heptanes, respectively. All new compounds were isolated in high yields as colourless, crystalline materials and characterised in solution by multinuclear NMR spectroscopy. Four representative examples were chosen for X-ray diffraction studies, thus providing the first structurally characterised ring systems of that size at a tetraalkyl borate centre.     

Synthesis and structure of tetrahydro-1,2-oxazine-n-dithiocarboxylic acid esters

New tetrahydro-1,2-oxazine-N-dithiocarboxylic acid esters were synthesized, and their structures were investigated by IR and PMR spectroscopy and mass spectrometry.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 454–458, April, 1976.     

Synthesis of pyrimidine betaines with phosphonium and cycloammonium cations

Previously undescribed pyrimidine betaines with cycloammonium and triphenylphosphonium cations were obtained. A study of the UV, IR, PMR, and mass spectra made it possible to draw a conclusion regarding the noncyclic structure of betaines stabilized by an intramolecular donor-acceptor interaction of the charge-transfer complex (CTC) type.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1687–1690, December, 1978.     

Mesomeric betaines of azolium azolate: Synthesis and properties

A facile entry into the almost unknown azolium azolate inner salts is described, and the structure of these highly dipolar compounds is well reflected by their spectroscopic properties and reactivity towards electrophiles (MeI) and dipolarophiles (DMAD) under mild conditions.     

Synthesis of new enantiomeric 1,2-diamines containing a myrtenyl fragment

Some new bi -and tridentate nitrogen-containing chiral ligands were synthesized on the basis of natural monoterpenoids, (+)-and (?)-myrtenals and (+)-myrtenol. A procedure was proposed for the synthesis of unsymmetrical ligands containing terpenoid and o-hydroxyphenyl fragments.