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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]

The reaction of MnCl2·4H2O with t-BuPO3H2 in the presence of triethylamine afforded the tridecanuclear cage, [MnIIMnIII 12(μ4-O)6(μ-OH)6(O3P–t-Bu)10(OH2)2(DMF)4]·[2MeOH·4DMF] (1). The structural analysis of 1 reveals that it is a mixed-valent complex containing a [MnIIMnIII 12(μ4-O)6] core. The centre of the core is occupied by a MnII ion which is surrounded by 12 MnIII ions. The latter are connected to each other by six μ-OH− and 10 t-BuPO3 2− ligands. The vacant coordination sites of six MnIII ions situated in the periphery are occupied by four DMF and two water molecules. Magnetic studies on 1 reveal a frequency-dependent response which is characteristic of single-molecule magnets. [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]