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A fluorapatite-supported palladium catalyst (PdFAP) was synthesized by treatment of fluorapatite (prepared by incorporating the basic species fluoride ion into apatite in situ by co-precipitation) with bis(benzonitrile)palladium(II) chloride in acetone. The catalyst displayed high catalytic activity for Suzuki coupling of aryl iodides and bromides with boronic acids at room temperature and chloroarenes at 130 8C in the presence of tetrabutylammonium bromide to give biaryls in excellent yields. Heck olefination of chloroarenes was also successfully carried out by this catalyst. PdFAP was recovered quantitatively by simple filtration and reused with consistent activity. PdFAP was well characterized by XRD, FTIR, XPS, ICP-AES, CO 2 TPD and CHN elemental analysis.

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Magnesium/lanthanum mixed oxide is an effective heterogeneous catalyst for aldol-type condensation of aldehydes and imines with ethyl diazoacetate (EDA) at room temperature in water to afford corresponding b-hydroxy-a-diazo carbonyl compounds and b-amino-a-diazo carbonyl compounds in good yields. The catalyst is recovered and reused for several cycles with consistent activity.Keywords: b-amino-a-diazo carbonyl compounds; b-hydroxy-a-diazo carbonyl compounds; heterogeneous catalyst; magnesium/lanthanum mixed oxide; water as solvent a-Diazo carbonyl compounds [1] are a potential source of amino alcohols and acids. a-Diazo carbonyl compounds are generally prepared by the azido transfer reaction of carbonyl compounds.[2] Condensation of acyldiazomethane to aldehydes and imines also yields a-diazo carbonyl compounds but requires deprotonation of the acyldiazomethane. This is usually carried out by using strong bases, such as butyllithium, [3] lithium diisopropylamide (LDA), [4] sodium hydride, [5] potassium hydroxide, [6] [7] and quarternary ammonium hydroxide.[8] However, some of the methods require low temperatures and absolutely anhydrous conditions, moreover the use of such strong bases may not be compatible with functional groups in the substrates. Thus, the development of more improved synthetic methods for the preparation of a-diazo carbonyl compounds remains an active research area.In recent years, there has been increasing emphasis on the use and design of environment-friendly solid catalysts to reduce the amount of toxic waste. The use of a solid catalyst allows easy separation of catalyst from the reaction mixture in large-scale production to conform to the concept of green technology. In a recent review, Sheldon [9] emphasized the point that "the best solvent is no solvent and if a solvent (diluent) is needed then water is preferred. Water is nontoxic, non-flammable, abundantly available and inexpensive" therefore, reactions performed in water are safer and cheaper.We herein report the synthesis of b-hydroxy-adiazo carbonyl compounds and b-amino-a-diazo carbonyl compounds by condensation of a wide variety of aldehydes and imines with ethyl diazoacetate using the Mg/La mixed oxide catalyst in water (Scheme 1).To the best of our knowledge, there are no reports on this condensation using a heterogeneous catalyst and water as solvent. The Mg/La mixed oxide catalyst was prepared by the co-precipitation method described earlier.[10] Chemical analysis of the solid gave the composition La 2 O 3 29.5 %, MgO: 30.1 %, K 2 O: 3.4 %, H 2 O: 37 %. The catalyst is well characterized by XRD, DTA coupled with mass spectrometry, FTIR and calorimetry. This mixed oxide is macroporous and shows a surface area of 37.6 m 2 g À1 after calcination at 923 K. Recently, we have efficiently performed transesterifications of diethyl carbonate by alcohols [11] and Michael addition reactions [10] by using this highly Scheme 1.