Facile synthesis of 2‐alkylthio‐5‐phenylmethylene‐4H‐imidazol‐4‐ones

2‐Alkylthio‐5‐phenylmethylidene‐4H‐imidazol‐4‐ones 4 were synthesized by S‐alkylation of 2‐thioxo‐3‐alkyl(aryl)‐4‐imidazolidinones 3 , which were obtained via cyclization of isothiocyanates 2 with aliphatic(aromatic) primary amines. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:348–351, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10160     

Cycloaddition of N‐(2,2,2‐trichloroethylidene)‐substituted carboxamides and carbamates to 1,2,4‐thiadiazol‐5(2H)‐imines

1,2,4‐Thiadiazol‐5(2H)‐imines 4 react with N‐(2,2,2‐trichloroethylidene)‐substituted amides 5 to form [3 + 2]‐cycloaddition products 6 featured by an extra coordination of the ring sulfur atom to the terminal nitrogen atom of the side 1,3‐diazapropenylidene group, as established by X‐ray diffraction investigation. This coordination evidently plays an important role in the alkylation of compounds 6 into 8 at the oxygen atom under mild conditions. The S N bond “switch‐over” restoring the original 1,2,4‐thiadiazole ring occurs therewith. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:474–480, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10182     

Crystallographic report: Crystal structure of 1‐bromo‐1′‐[(2S)‐N‐(1‐hydroxy‐3‐methylbutane‐2‐yl)]‐ferroceneamide

For the unsymmetrical title compound, 1‐bromo‐1′‐[(2S)‐N‐(1‐hydroxy‐3‐methylbutane‐2‐yl)]‐ferroceneamide, two independent molecules were found in the asymmetric unit. Copyright © 2003 John Wiley & Sons, Ltd.     

Crystallographic report: Chloro(N,N‐diethyldithiocarbamato)(4,7‐dimethyl‐1, 10‐phenanthroline)mercury(II) hemi‐chloroform solvate

The X‐ray crystal structure of Hg(S₂CNEt₂)(4,7‐Me₂‐phen)Cl features an essentially four‐coordinate geometry for mercury within a ClN₂S donor set that defines a distorted tetrahedral arrangement. Copyright © 2003 John Wiley & Sons, Ltd.     

A convenient synthesis of 5‐(O,O‐dialkylphosphoryl)‐4‐aryl‐3,4‐dihydropyrimidin‐2(1H)‐ones

A general and convenient route for the synthesis of dihydropyrimidines bearing the phosphoryl moiety by a one‐pot cyclocondensation involving aldehydes, urea, and O,O‐dialkyl‐2‐oxo‐propanephosphonates, using ytterbium triflate as catalyst, is reported. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:13–17, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10058     

Photoinduced and thermally induced cationic polymerizations using S,S‐dialkyl‐S‐(3,5‐dimethylhydroxyphenyl)sulfonium salts

A study of the photoinitiated and thermally initiated cationic polymerizations of several monomer systems with S,S‐dialkyl‐S‐(3,5‐dimethylhydroxyphenyl)sulfonium salt (HPS) photoinitiators bearing different lengths of alkyl chains on the positively charged sulfur atom has been conducted. HPS photoinitiators are capable of photoinitiating the cationic polymerization of a wide variety of epoxy and vinyl ether monomers directly on irradiation with short‐wavelength UV light. Aryl ketone photosensitizers are effective in extending the spectral response of these photoinitiators into the long‐wavelength UV region. Kinetic studies with real‐time infrared spectroscopy show that HPS photoinitiators exhibit good efficiency in the polymerization of epoxide and vinyl ether monomers. Comparative studies also demonstrate that S,S‐dimethyl‐S‐(3,5‐dimethyl‐2‐hydroxyphenyl)sulfonium salts are more active photoinitiators than their isomeric S,S‐dimethyl‐S‐(3,5‐dimethyl‐4‐hydroxyphenyl)sulfonium salt counterparts. Both types of HPS photoinitiators display reversible photolysis as a result of facile termination reactions that take place between the growing chains ends with the photogenerated sulfur ylides. Preliminary studies have shown that HPS photoinitiators can also be employed as thermal initiators for the cationic ring‐opening polymerization of epoxides at moderate temperatures. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2570–2587, 2003     

Efficient synthesis and dehydration reaction of trichloromethylated 2‐(3‐phenyl‐5‐hydroxy‐4,5‐dihydro‐1H‐pyrazol‐1‐yl)‐4‐aryl‐5‐alkylthiazoles

A convenient method for the synthesis of a novel series of 11, specifically substituted, noncondensed 5,5‐bicycles 2‐[3‐phenyl‐5‐hydroxy‐5‐trichloromethyl‐4,5‐dihydro‐1H‐pyrazol‐1‐yl]‐4‐aryl‐5‐alkylthiazoles ( 3a–k ; 65–94% yield) from the reactions of 3‐phenyl‐5‐hydroxy‐5‐trichloromethyl‐4,5‐dihydro‐1H‐1‐pyrazolethiocarboxyamide ( 1 ) with substituted 2‐bromo‐4′‐acetophenones ( 2a–f ) and 2‐bromo‐4′‐propiophenones ( 2g–k ) is reported. Dehydration of compounds 3a–k with a mixture of concentrated sulfuric acid/chloroform furnished the corresponding 2‐[3‐phenyl‐5‐trichloromethyl‐1H‐pyrazol‐1‐yl]‐4‐aryl‐5‐alkylthiazoles ( 4a–k ) in good yields (61–93%). © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:132–137, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10113     

Cycloaddition of bis‐1,3‐dipolar reagents to 1,3‐diarylprop‐2‐en‐1‐ones

Bis pyrazolines and isoxazolines were prepared by 1,3‐dipolar cycloaddition of benzene‐1,3/1,4‐dicarboxaldehyde dihydrazones and dioximes to 1,3‐diaryl‐prop‐2‐en‐1‐ones. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:379–383, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10169     

Synthesis and complete NMR characterization of 4‐alkyl‐2‐(6‐substituted‐1,3‐benzoxazol‐2‐yl)benzenols

This paper describes the complete assignment of all carbons and hydrogens of several newly synthesized 6‐substituted 2‐(2‐hydroxyaryl)benzoxazoles from 2,2′‐dihydroxydiaryl Schiff bases by the use of two‐dimensional NMR techniques. Copyright © 2003 John Wiley & Sons, Ltd.     

3‐Methylthio‐pyrano[4,3‐c]pyrazol‐4(2H)‐ones from 3‐(bis‐methylthio)methylene‐2H‐pyran‐2,4‐diones and hydrazines

A useful synthesis of 3‐methylthio‐6‐methyl‐pyrano[4,3‐c]pyrazol‐4(2H)‐ones via 3‐(bis‐methylthio)methylene‐5,6‐dihydro‐6‐alkyl(aryl)‐2H‐pyran‐2,4‐dione with hydrazine as well as methyl and phenyl hydrazines is described and the mechanism of the formation is discussed. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:342–344, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10158     

2,2,2‐triaryl‐4‐oxo‐1,3,2‐benzoxazastibinines

The hitherto unreported 4‐oxo‐1,3,2‐benzoxazastibinines 2 have been synthesized by the cyclization of disodium salt of salicylanilide ( 1 ) with Ar₃SbBr₂ (Ar = Ph, p‐tolyl, or mesityl). These compounds have been characterized by elemental analyses, molecular weight determination, and by IR, far IR, ¹H, and ¹³C NMR spectral studies. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:622–624, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10202     

Transition‐metal‐catalyzed reactions of 5‐methylene‐2‐oxazolidinone and 5‐methylene‐1,3‐thiazolidine‐2‐thione with isocyanates

5‐Methylene‐2‐oxazolidinone (1) and 5‐methylene‐1,3‐thiazolidine‐2‐thione (4) react with various isocyanates to give the corresponding urethanes 3 and 5 in high yields in the presence of palladium(0) or palladium(II) catalyst under mild reaction conditions. A mechanism is proposed. Copyright © 2003 John Wiley & Sons, Ltd.     

1,3,4‐Thia‐ and ‐selenadiazole and 1,2,4‐triazolo[4,3‐a]pyrimidine derivatives from hydrazonoyl halides

1,2,4‐Triazolo[4,3‐a]pyrimidines, thiadiazolines, selenadiazolines, and unsymmetrical azines were synthesized via reactions of a 4‐isopropylbenzoyl bromide 4‐nitrophenylhydrazone with each of potassium thiocyanate, potassium selenocyanate, ethyl 6‐methyl‐4‐[4‐(methylethyl)phenyl]‐2‐methylthio‐3,4‐dihydropyrimidine‐5‐carboxylate, and alkyl carbodithioate. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:421–426, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10156     

Photodesulfurization of 2,4‐diaryl‐1,2, 4‐triazole‐3‐thiones

Irradiation of triazole thiones in thin‐film reactor furnished the corresponding desulfurized triazoles in good yield. The required triazole thiones were synthesized from the respective acid hydrazide and isothiocyanate. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:269–272, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10140     

Synthesis and antimicrobial activity of N‐substituted N′‐[6‐methyl‐2‐oxido‐1,3,2‐dioxaphosphinino(5,4‐b)pyridine‐2‐yl]ureas

N‐Substituted N′‐[6‐methyl‐2‐oxido‐1,3,2‐dioxaphosphinino(5,4,‐b)pyridine‐2‐yl]ureas have been accomplished by condensation of equimolar quantities of chlorides of various carbamidophosphoric acids ( 3 ) with 3‐hydroxyl‐6‐methyl‐2‐pyridinemethanol (lutidine diol) ( 4 ) in the presence of triethylamine in dry toluene–tetrahydrofuran (1:1) mixture at 45–50°C. Their structures were established by elemental analyses, IR, ¹H NMR, ¹³C NMR, and ³¹P NMR spectral data. Their antifungal and antibacterial activity is also evaluated. Most of these compounds exhibited moderate antimicrobial activity in the assays. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:509–512, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10181     

Synthesis and characterization of second‐generation S,S‐dialkyl‐S‐(dimethylhydroxyphenyl)sulfonium salt photoinitiators

A new, simplified method has been developed for the synthesis of S,S‐dialkyl‐S‐(dimethylhydroxyphenyl)sulfonium salt cationic photoinitiators. This novel method has successfully been used for the preparation of S,S‐dialkyl‐S‐(3,5‐dimethyl‐4‐hydroxyphenyl)sulfonium and S,S‐dialkyl‐S‐(3,5‐dimethyl‐2‐hydroxyphenyl)sulfonium salts showing a wide variation in the length and structure of the alkyl chains on the positively charged sulfur atom. These photoinitiators can also be prepared with a wide variety of different anions. The manipulation of the lengths of the alkyl chains permits the design of compatible photoinitiators for highly nonpolar monomers and oligomers such as epoxy‐functional silicones, epoxidized polybutadiene, and epoxidized vegetable oils. This article describes the synthesis and characterization of these photoinitiators. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2556–2569, 2003     

Reaction of ω‐carbonyl substituted 1,3,3‐trimethyl‐2‐methyleneindolines with phosphorus(III) halides

The phosphorylation of N‐benzoyl‐2‐(1,3,3‐trimethyl‐2‐methyleneindoline)acetamide ( 2 ) and ω‐(3‐dimethylamino)benzoyl‐1,3,3‐trimethyl‐2‐methyleneindoline ( 6 ) with phosphorus(III) halides resulted in the formation of 2,3‐dihydro‐4H‐1,5,2‐oxazaphosphinin‐4‐one and 1,2‐dihydro‐3H‐phosphindol‐3‐one systems, respectively. The properties of the obtained compounds were studied. Further cyclization of 1,2‐dihydro‐3H‐phosphindol‐3‐one into dihydrophosphindolo[3,2‐c]pyrazole was carried out. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:23–28, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10060     

Conversion of 2(3H)‐furanones into 1,3,4‐oxadiazoles

A series of 2‐phenyl‐5‐alkenyl‐1,3,4‐oxadiazoles were synthesized in high yields from the corresponding dicarbonylhydrazides through cyclodehydration. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:570–574, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10197     

A novel pattern of dimerization for 1, 4‐diphospha‐1,3‐butadienes

A new example of [2+4] cycloaddition of the low‐coordinated diphospha‐analog of butadiene protected with a 2,4‐di‐tert‐butyl‐6‐methylphenyl group has been described. X‐ray structure investigations of monomer 4b and dimer 5a have been reported for the first time. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:231–234, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10123     

Synthesis of 3′‐1,2,4‐triazolo‐ and 3′‐1,3,4‐thiadiazoliminothymidines

New 5′‐acetyl‐3′‐1,3,4‐thiadiazoliminothymidines 11, 14 were prepared, via spontaneous rearrangments, by cycloaddition of 5′‐acetyl‐3′‐deoxy‐3′‐isothiocyanatothymidine 9 with 1‐aza‐2‐azoniaallene hexachloantimonates. Similary, 3′‐cyano analogue 19 was reacted with the same cumulenes to furnish 3′‐1,2,4‐triazolo‐thymidines 22, 24 , and 26 . Deblocking of the acylated products afforded the free nucleosides. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:298–303, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10146