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The reaction of bis(tri- n-butyltin)oxide, [ nBu3Sn]2O, with HO2C-C6H4-4-CF3 (RfTol-CO2H) affords a coordination polymer [ nBu3SnO2C-RfTol] n ( 1). 1 undergoes hydrolysis in the presence of atmospheric moisture, at room temperature, resulting in the formation of the diorgano stannoxane [{ nBu2SnO2C-RfTol}2O]2 ( 2). The transformation of 1 to 2 is accompanied by a Sn-C bond cleavage reaction. Formation of 2 also occurs in a direct reaction, involving [ nBu3Sn]2O and RfTol-CO2H in the presence of water. 2 can also be prepared in a 1:1 reaction of di- n-butyltin oxide, [ nBu2SnO] n with RfTol-CO2H. The conversion of 2 from 1 was monitored by 119Sn NMR spectroscopy over a period of eight days. The molecular structure of 2 reveals a tetranuclear assembly consisting of two pairs of structurally distinct six-coordinate tin atoms. Extensive hydrogen-bonding interactions (C-H ···O, C-H ···F) and weak F ···F interactions involving organo-fluorine atoms in the crystal structure result in the formation of a three-dimensional supramolecular architecture for 2. [ABSTRACT FROM AUTHOR]

An efficient one-pot protocol for the synthesis of multi-substituted 2-pyrone derivatives from internal alkynes and unactivated alkenes is reported. The methodology involves difunctionalization of internal alkynes by using Pd(II) as a catalyst alongwith X-Phos as ligand via 6- endo transesterification and subsequent alkenylation pathway. Notable features include simple and easily available starting materials, including a range of unactivated alkenes, reduced synthetic steps and mild reaction conditions with high efficiency. [ABSTRACT FROM AUTHOR]

Abstract: Various phosphorus-supported fluorescent probes have been synthesized by the condensation reaction of multi-functional phosphorus hydrazides with various fluorophore-containing carboxaldehydes. Compounds, thus prepared, in this study are (PhO)2P(O)[N(Me)–N;R] (1a, 1b), Ph2P(O)[N(Me)–N;R] (2b, 2c, 2d), PhP(O)[N(Me)–N;R]2 (3b, 3c), P(S)[N(Me)–N;R]3 (4b, 4c), P(O)[N(Me)–N;R]3 (5a, 5b, 5c), N3P3(O2C12H8)2[N(Me)–N;R]2 (6a, 6b, 6c), N3P3(O2C12H8)[N(Me)–N;R]4 (7a, 7b, 7c, 7d) and N3P3[N(Me)–N;R]6 (8b, 8c), where R=1-pyrenyl (a), 9-anthracenyl (b), 9-phenanthryl (c) and 7-(N,N′-diethylamino)-3-coumarinyl (d). All of these compounds have been characterized by various analytical techniques including 31P{1H} NMR spectroscopy. Compounds 1b, 2b, 3b, 4b, 5b, 5c and 6d have also been characterized by single crystal X-ray analysis. All of these phosphorus-supported compounds exhibit excellent fluorescence properties in aqueous solution at near physiological conditions. [Copyright &y& Elsevier]