One‐pot three components synthesis of alkyl indeno [1,2‐b]‐quinoxalin‐11‐ylideneacetates in water and under solvent‐free conditions

We introduced a very simple, one‐pot three component procedure for preparation of alkyl indeno[1,2‐b]quinoxalin‐11‐ylideneacetates 4 from reaction of ninhydrin 1 , phenylenediamines 2 , (alkoxycarbonylmethyl)triphenylphosphonium bromides 3 , and sodium acetate in water and under solvent‐free conditions. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:549–552, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20136     

Synthesis and herbicidal activity of 2‐alkyl(aryl)‐3‐methylsulfonyl(sulfinyl)pyrano‐ [4,3‐c]pyrazol‐4(2H)‐ones

Useful oxidation reaction of 2‐alkyl(aryl)‐3‐methylthiopyrano[4,3‐c]pyrazol‐4(2H)‐ones, leading to either the corresponding sulfoxides or sulfones, using hydrogen peroxide and acetic acid in 1,2‐dichloroethane, is described. Bioassay results showed that the products have some herbicidal activity. © 2005 Wiley Periodicals, Inc. 16:255–258, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20067     

Microwave‐assisted from synthesis of 2‐arylamino‐2‐imidazolines on a solid support

An efficient synthesis of 2‐arylamino‐2‐imidazolines from dimethyl N‐aryldithioimidocarbonates and ethylenediamine on solid support under microwave irradiation has been developed. The reaction time has been reduced from hours to minutes with improved yields as compared to conventional heating. Their piperidin‐4‐ylmethyl and morpholin‐4‐ylmethyl derivatives were synthesized by treatment with formaldehyde and piperidine or morpholine. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:142–222, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20081     

Synthesis of 3‐substituted 2‐trifluoro(trichloro)methyl‐2H‐chromenes by reaction of salicylaldehydes with activated trihalomethyl alkenes

The reaction of activated trihalome‐ thylsubstituted alkenes with salicylaldehydes in the presence of triethylamine gives 3‐substituted 2‐trifluo‐ romethylchroman‐4‐ols and 2‐trifluoro(trichloro)methyl‐2H‐chromenes in high yields. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:492–496, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20146     

Synthesis and hydrolysis of p‐toluoyl and acetyl 9‐triptycyl diselenides: A study on generation of triptycene‐9‐selenenoselenoic acid

p‐Toluoyl 9‐triptycyl diselenide ( 9 ) was prepared by reaction of Se‐9‐triptycyl triptycene‐9‐selenoseleninate ( 7 ) with p‐toluenecarboselenoic acid ( 8 ) and by reaction of triptycene‐9‐selenenoselenolate salt with p‐toluoyl chloride. Acetyl 9‐triptycyl diselenide ( 13 ) was prepared by reaction of triptycene‐9‐selenenoselenolate salt with acetyl chloride. Hydrolysis of the two diselenides, 9 and 13 , provided triptycene‐9‐selenol ( 10 ) and di‐9‐triptycyl triselenide ( 12 ), suggesting the generation of triptycene‐9‐selenenoselenoic acid ( 3 ). © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:525–528, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20155     

New 7‐phosphanorbornenes derived from 2‐methyl‐1‐phenyl‐ and 1‐cyclohexyl‐3‐ methyl‐2,5‐dihydro‐1H‐phosphole 1‐oxides

Novel 7‐phosphanorbornene derivatives, such as 4, 5, 10 , and 11 were synthesized utilizing 1‐phenyl‐2‐methyl‐2,5‐dihydro‐1H‐phosphole oxide ( 1 ) and 1‐cyclohexyl‐3‐methyl‐2,5‐dihydro‐1H‐phosphole oxide ( 7 ) as the starting materials. Products 4 and 10 were prepared by trapping the corresponding phosphole oxide intermediates ( 3 and 9 , respectively) by N‐phenylmaleimide, while 5 and 11 were obtained by the dimerization of 3 and 9 , respectively. The trapping reaction was studied in details; on one hand, bromo‐2,3‐dihydro‐1H‐phosphole oxides ( 6‐1 and 6‐2 ) were pointed out as the intermediates, on the other hand, the trapping reaction was optimized. Bri‐ dged P‐heterocycles 4, 5, 10 , and 11 were tested in the fragmentation‐related phosphorylation of methanol. Hydrogenation of phosphanorbornenes 4 and 5 led to the corresponding phosphanorbornanes ( 12 and 14 , respectively) and to a reductive type of retro cycloaddition. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:320–326, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20097     

Preparation of 2‐aminobenzophenones and polysubstituted quinolines through SmI2 promoted reductive cleavage of 3‐aryl‐2,1‐benzisoxazoles

Promoted by SmI₂, 3‐aryl‐2,1‐benzi‐ soxazoles underwent reductive cleavage of the N O bond leading to 2‐aminobenzophenones in high yields upon protonation. Otherwise, if ketones with active methylene group were added to the reaction mixture prior to protonation, the desired polysubstituted quinolines could be obtained under mild conditions in a one‐pot manner. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:637–643, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20164     

2,4,5‐Substituted furan‐3(2H)‐ones: Synthesis,reactions with amino acid and hydrazine derivatives

Furan‐3(2H)‐ones ( 3 ) were obtained from some 2,3‐dihydro‐furan‐2,3‐diones with a few Wittig reagents ( 2 ). The compounds of 3 with glycin and hydrazines ( 4a,b ) produced 2,3‐dihydro‐1H‐pyrrol‐3‐ones ( 5a–d ). All the reaction mechanisms were discussed by utilizing the similar reaction pathways. Structures of these compounds were determined by the IR, NMR, elemental analysis, and X‐ray diffraction method. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:235–241, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20115     

Synthesis and characterization of some new 4,4′‐(1,4‐phenylene)dipyrimidine and 6,6′‐(1,4‐phenylene)‐di(pyridin‐2(1H)‐one) derivatives

A series of new 4,4′‐(1,4‐phenylene)dipyrimidines 5a–c, 8a–c , and 10a,b have been synthesized from the reaction of amidines 1a–c with the dienaminone 2 , bis‐chalcone 6 , or ylidenemalono‐ nitrile 9 . The reaction of malononitrile and ethyl cyanoacetate with 2 gave 6,6′‐(1,4‐phenylene)di(pyridin‐2(1H)‐ones) ( 15a,b ). The structures of the products were proved by elemental analyses, IR, MS, ¹H, and ¹³C NMR spectroscopy. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:507–512, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20150     

2‐Benzothiazolyl‐N‐(arenesulfonyl)‐sulfinimidoyl fluorides

2‐Benzothiazolyl‐N‐(arenesulfonyl)‐sulfinimidoyl fluorides were synthesized by the treatment of benzothiazolyl‐2‐sulfur trifluoride with sulfonamides. The reaction of 2‐benzothiazolyl‐N‐ (p‐toluenesulfonyl)‐sulfinimidoyl fluoride with tert‐ butylamine and morpholine gave 2‐benzothiazolyl‐ N‐(arenesulfonyl)‐sulfinimidoyl amides. The reaction of 2‐benzothiazolyl‐N‐(p‐toluenesulfonyl)‐sulfinimi‐ doyl fluoride or 2‐benzothiazolyl‐¹⁵N‐(p‐tosyl)sul‐ finimidoyl fluoride with S‐trimethylsilylbenzenethiol gave di(benzothiazolyl‐2) disulfide, fluorotrimethylsi‐ lane and N,N′‐bis(p‐toluenesulfonyl)‐N,N′‐bis(phenyl‐ thio)‐hydrazine or ¹⁵N,¹⁵N′‐bis(p‐toluenesulfonyl)‐¹⁵N, ¹⁵N′‐bis(phenylthio)‐hydrazine, respectively. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:352–356, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20102     

Synthesis of novel chiral 2‐oxo‐ and 2‐thio‐1,3,2‐oxazaphospholidines via asymmetric cyclization of L‐methionol with (thio)phosphoryl dichlorides

In order to search for novel antitumor and antiviral agents with high activity and low toxicity, a series of chiral 2‐thio(oxo)‐1,3,2‐oxazaphospholidines were synthesized via the reaction of L ‐methionol with all kinds of (thio)phosphoryl dichlorides in THF in the presence of triethylamine at room temperature. The structures of all of the new compounds were confirmed by elemental analyses, ¹H, ³¹P NMR, and IR spectra. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:33–38, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20060     

Short communication: An alternative and effective catalyst in the stereo‐specific reaction of Z‐1‐aryl‐1‐stannyl‐2‐silylethenes with allyl bromide

The Pd(dba)₂‐catalyzed reaction of Z‐1‐aryl‐1‐(tributylstannyl)‐2‐(trimethylsilyl)ethenes with allyl bromide in the presence of copper(I) iodide is reported for the first time. The reaction in the presence of 0.5 mol% Pd(dba)₂ and 8 mol% CuI in dimethylformamide takes place at room temperature to give E‐2‐aryl‐1‐(trimethylsilyl)penta‐1,4‐dienes exclusively in isolated yields of 62–99%. A putative reaction mechanism is proposed. Copyright © 2005 John Wiley & Sons, Ltd.     

Ab initio study of reactions of 1‐halogen‐3‐methoxy‐1‐propynes with Grignard reagent

The structures of coordination complexes of methylmagnesium chloride with 1‐halogen‐3‐methoxy‐1‐propynes have been studied by means of ab initio methods (RHF/3‐21G*, RHF/6‐31G* and RHF/6‐31G**), taking into account the electron correlation by Møller‐Plesset perturbation theory (MP2). Two pathways of the nucleophilic halogen substitution reaction between the reagents have been considered. The calculations predict the addition–elimination mechanism as advantageous for the reaction. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005     

Preparation and cyclization of 4‐chloro‐5,5‐dimethyl‐3‐formyl‐1,2‐oxathiolene 2,2‐dioxide

Chloroformylation of 5,5‐dimethyl‐1,2‐ oxathiolan‐4‐one 2,2‐dioxide 4 with Vilsmeier reagent (DMF/POCl₃) led to the formation of cyclic β‐chloro‐vinylaldehyde (4‐chloro‐5,5‐dimethyl‐3‐formyl‐1,2‐oxathiolene 2,2‐dioxide 5 ). Compound 5 reacted with formamidine, o‐aminophenol, 1,2‐phenylenediamine, aminopyrazole, and aminotetrazole to give the corresponding heterocyclic compounds. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:200–204, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20094     

Synthesis and characterization of poly(DTC‐b‐PEG‐b‐DTC) triblock and poly(TMC‐b‐DTC‐b‐PEG‐b‐DTC‐b‐TMC) pentablock copolymers and kinetics of the polymerization

Dihydroxyl capped biodegradable poly(DTC‐b‐PEG‐b‐DTC) (BCB) triblock copolymer and poly(TMC‐b‐DTC‐b‐PEG‐b‐DTC‐b‐TMC) (ABCBA) pentablock copolymer have been synthesized by PEG and BCB copolymer as macroinitiator in the presence of yttrium tris(2,6‐di‐tert‐butyl‐4‐methylphenolate). The copolymers without random segments have been thoroughly characterized by ¹H, ¹³C‐NMR, SEC, and DSC. Molecular weights of the obtained copolymers are dependent on the amount of PEGs and coincide with the theoretical values. The exchange reaction of yttrium alkoxide and hydroxyl end group is essential for controlling the products' molecular weight. Their thermal behaviors are relevant to the chain lengths of PEG and PDTC segments. The Monte Carlo method has been developed to estimate the chain propagation constant and exchange reaction constant. In average, one exchange reaction will occur after approximately six monomer molecules insert into the growing chain. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1787–1796, 2005     

Using the 1,2‐dihydro‐1,2‐diphosphinine ring as a template for the synthesis of new bicyclic structures and new trans‐chelating bis‐phosphines

The 1,2‐dihydro‐1,2‐diphosphinine decacarbonylditungsten complex 1 has been used as a synthetic equivalent of the corresponding 1,2‐dianion 2 . These two 1,2‐positions can be linked by a (CH₂)₄ bridge to yield a [4.4.0] bicyclic structure 6 whose identity has been confirmed by X‐ray crystal structure analysis. Alternatively, two ω‐iodohexyl chains can be grafted onto these positions and the resulting diiodo derivative 9 transformed into a long‐chain bis‐phosphine 10 by reaction with lithium diphenylphosphide. This bis‐phosphine gives a chelate complex with PdCl₂ whose trans‐stereochemistry was established by X‐ray crystal structure analysis. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:44–48, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20073     

Facile synthesis of 2‐alkylthio‐3‐amino‐4 H‐imidazol‐4‐ones and 2H‐imidazo[2,1‐b]‐1,3,4‐thiadiazin‐6(7H)‐ones via N‐vinylic iminophosphorane

2‐Alkylthio‐3‐amino‐4H‐imidazol‐4‐ ones 5 were synthesized by S‐alkylation of 2‐thioxo‐3‐amino‐4‐imidazolidinones 4 , which were obtained via cyclization of isothiocyanates 2 with hydrazine hydrate. 5l–n reacted with Ph₃P, C₂Cl₆, and NEt₃ to give 2H‐imidazo[2,1‐b]‐1,3,4‐thiadiazin‐ 6(7H)‐ones 7a–c in good yields. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:76–80, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20069     

Toughening of nylon‐6 with epoxy‐functionalized acrylonitrile‐butadiene‐styrene copolymer

Glycidyl methacrylate (GMA) functionalized acrylonitrile‐butadiene‐styrene (ABS) copolymers have been prepared via an emulsion polymerization process. The epoxy‐functionalized ABS (e‐ABS) particles were used to toughen nylon‐6. Molau tests and FTIR results showed the reactions between nylon‐6 and e‐ABS have taken place. Scanning electron microscopy (SEM) displayed the compatibilization reaction between epoxy groups of e‐ABS and nylon‐6 chain ends (amine or carboxyl groups), which improve disperse morphology of e‐ABS in the nylon‐6 matrix. The presence of only a small amount of GMA (1 wt %) within the e‐ABS copolymer was sufficient to induce a pronounced improvement of the impact strength of nylon‐6 blends; whereas further increase of the GMA contents in e‐ABS resulted in lower impact strength because of the crosslinking reaction between nylon‐6 and e‐ABS, resulting in agglomeration of the ABS particles. SEM results showed shear yielding of the nylon‐6 matrix and cavitation of rubber particles were the major toughening mechanisms. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2170–2180, 2005     

PH‐functional o‐phosphinophenols— synthesis via methoxymethylethers and screening tests for Ni‐catalyzed ethylene polymerization

Various primary and secondary 2‐phosphinoaryl methoxymethylethers were prepared via orthometallation of methyl‐ and methoxy‐substituted aryl methoxymethylethers and subsequent reaction with aminochlorophosphines, followed by alcoholysis and reduction with excess LiAlH₄. Incomplete reduction provides 2‐methoxymethoxy‐substituted cyclotetraphosphines, isolated and characterized by X‐ray crystal structure analysis in one case. An example of the facile P‐alkylation of primary to secondary representatives is also given. Secondary 2‐phosphinophenols, obtained by selective cleavage of the MOM‐protection group, and even the primary 2‐phosphino‐4‐methylphenol react with Ni(COD)₂ to form ethylene polymerization catalysts. 4‐Methoxy groups cause a strong increase of the molecular weights and a bimodal molecular weight distribution of the polymerization products; neither effect is observed for tertiary phosphinophenolate/Ni polymerization catalysts. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:379–390, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20107     

Reaction of tellurium tetraiodide with 2,3‐dihydro‐1,3‐diisopropyl‐4,5‐dimethylimidazol‐2‐ylidene

2,3‐Dihydro‐1,3‐diisopropyl‐4,5‐dimethylimidazol‐2‐ylidene 1 (Carb, R¹ = ⁱPr, R² = Me) reacts with TeI₄ to give the carbene adduct CarbTeI₂ ( 3 ). The crystal structure of 3 consists of T‐shaped monomeric fragments linked by weak Te. I interactions to form infinite helical chains. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:316–319, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20090