"Phosphorus, Sulfur, and Silicon and the Related Elements"

Keglevich, György; Karaghiosoff, Konstantin; Rudd, Martin D.

doi: 10.1080/10426507.2014.921802pmid: N/A

Rudd, Martin D.

doi: 10.1080/10426507.2014.906809pmid: N/A

Holmes, Robert

doi: 10.1080/10426507.2014.921803pmid: N/A

Yu, Valentina K.; Berlin, K. Darrell; Iskakova, Tynyshtyk K.; Faskhutdinov, Marat F.; Praliyev, Kaldybay D.; Lee, Chengeer P.; Ten, Assel Yu.; Malmkova, Aigul Ye.

doi: 10.1080/10426507.2014.903483pmid: N/A

AbstractBased upon the analysis of 1H NMR data, along with molecular modeling, it was shown that the reduction of 3,7-dihetera(N,N-; N,O-; N,S-)bicyclo[3.3.1]nonan-9-ones by LiAlH4 led to a mixture of two stereoisomeric secondary alcohols with different orientations of the hydroxyl groups in one of the ring systems. Diaza derivatives in deuterochloroform exist in predominant chair-boat conformations. However, the replacement of nitrogen in one of the heterocycles by oxygen or sulfur led to stereoisomers one of which existed in chair-boat conformation and another in a chair–chair conformation. In all cases the boat conformation is stabilized by formation of an intramolecular hydrogen bond (IMHB) between a lone electron pair of the nitrogen atom and a proton on the pseudo axial hydroxyl group of the other ring.

Brahmachari, Goutam; Laskar, Sujay

doi: 10.1080/10426507.2014.903484pmid: N/A

AbstractA facile and efficient protocol for one-pot three-component synthesis of structurally diverse (2-amino-3-cyano-4H-chromen-4-yl)phosphonic acid diethyl esters from the reaction of salicylaldehydes, malononitrile (or ethyl cyanoacetate), and triethylphosphite using basic nanocrystalline MgO as catalyst in aqueous ethanolic medium at room temperature has been developed. Nano-MgO has been prepared using a simple sol-gel approach. Clean reaction profile, easy reusability of MgO nano-catalyst, mild reaction condition, good yields, and practical applicability are the major advantages of the present protocol.

Sogani, Nidhi; Maheshwari, Pooja; Bansal, Raj K.

doi: 10.1080/10426507.2014.903486pmid: N/A

AbstractAn overview of 2-phosphaindolizines, i.e. 1,3-azaphospholo[1,5-a]pyridines along with their 1-aza-, 3-aza- and 1,3-diaza analogues has been presented. It includes their methods of syntheses, characterization and reactions. Under reactions, electrophilic substitutions, N-alkylation, Diels-Alder (DA) reactions with the >C=P- functionality in the absence of the catalyst and also in the presence of the catalyst, other 1,2-additions across the >C=P- functionality, cheletropic cycloaddition of tetrachloro-o-benzoquinone (TCQ) with the phosphorus atom and co-ordination with the metal pentacarbonyls and other derivatives have been described.

Ho, Feny; Li, Yongxin; Ganguly, Rakesh; Mathey, François

doi: 10.1080/10426507.2014.903487pmid: N/A

AbstractDFT computations suggest that terminal allylphosphinidene pentacarbonyltungsten complex 1 can evolve either by intramolecular P + C˭C cycloaddition or by [1,2] H C to P shift to give 2 or 6. Upon thermolysis of the 7-allyl-7-phosphanorbornadiene precursor, the transient complex 1 gives two diastereomeric dimers 4a,b deriving from a head-to-tail P + C˭C intermolecular cycloaddition and another dimer 5 deriving from the [4 + 1] cycloaddition of 1 with 6, followed by an intramolecular hydrophosphination.

Ahankar, Hamideh; Ramazani, Ali; Ahmadi, Yavar

doi: 10.1080/10426507.2014.903488pmid: N/A

AbstractReactions of N-isocyaniminotriphenylphosphorane with cyclopentanone in the presence of an E-cinnamic acid derivative and a primary amine proceeds smoothly at room temperature and in neutral conditions to afford sterically congested 1,3,4-oxadiazole derivatives in high yields. The reaction proceeds smoothly and cleanly under mild conditions and no side reactions were observed.

Heinl, Sebastian; Balázs, Gábor; Scheer, Manfred

doi: 10.1080/10426507.2014.903489pmid: N/A

AbstractA new synthesis of [CpBIGFe(CO)2]2 3 (CpBIG = C5(4-nBuC6H4)5) was developed starting from CpBIGNa and FeCl2 in the presence of CO. Reaction of this product with P4 leads to the two new Pn ligand complexes [CpBIGFe(η5-P5)] 1b and [(CpBIGFe)2(μ,η4:4-P4)] (4) containing the highly sterically demanding CpBIG ligand. Depending on the solvent, different ratios of 1b:4 are obtained. The products 1b, 3, and 4 were characterized by spectroscopic methods as well as by X-ray diffraction.

Procházková, Soňa; Böhmová, Zuzana; Kubíček, Vojtěch; Kotek, Jan; Hermann, Petr; Lukeš, Ivan

doi: 10.1080/10426507.2014.904864pmid: N/A

AbstractAnalogues of iminodiacetic acid (H2IDA) and nitrilotriacetic acid (H3NTA) bearing two (hydroxomethyl)methylphosphinate or (2-carboxyethyl)methylphosphinate groups were synthesized. Their acid-base and coordination properties with divalent metal ions (Cu2+, Ni2+ and Zn2+) were studied by potentiometry. The compounds exhibit very low basicity of the amino groups (pKa = 6.2–7.6) due to presence of two electron-withdrawing methylphosphinate groups and, consequently, a low stability of the complexes. In the case of IDA-analogues, the low complex stability results in precipitation of metal hydroxides in neutral region. As expected, NTA-analogues form more stable complexes and, thus, they were also studied in the alkaline region. Presence of additional carboxylate in the 2-carboxyethylphosphinic acid groups results in the formation of dinuclear complexes. Solid-state structures of two compounds were determined by X-ray diffraction analysis. The compounds are protonated on the nitrogen atom and the structures are stabilized by rich hydrogen bond network.