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Alpha,beta-unsaturated esters were obtained with complete control of stereoselectivity utilizing a sequential reaction of dichloroesters with a variety of aldehydes, promoted by active manganese. This methodology is generally applicable, and the C-C double bond can be di- or trisubstituted. A mechanism based on a successive aldol-type reaction/beta-elimination is proposed to explain these results.

A new divalent cadmium phosphonate, Cd2Cl2(H2O)4(H2L), has been synthesized from the ethylenediamine-N,N'-bis(methylenephosphonic acid) (H4L). The obtained microcrystalline compound has been characterized by solid-state IR spectra and 13C, 31P, and 113Cd CP MAS NMR. The static 13P NMR spectra have been also recorded to give the delta11, delta22, and delta33 chemical shift parameters for both compounds. The spectral data, collected for Cd2Cl2(H2O)4(H2L), are in an agreement with its X-ray powder diffraction structure solved with the cell dimensions a = 16.6105(10), b = 7.1572(4), and c = 6.8171(4) A and beta = 98.327(4) degrees. The octahedral coordination sphere of the cadmium atoms consists of two phosphonate oxygen atoms, two water oxygen atoms, and the two chlorine atoms. Cadmium atoms are bridged by the chlorine atoms forming four-membered rings. The phosphorus atoms exhibit a tetrahedral coordination with two oxygen atoms bonded to the cadmium atoms with P-O distances of 1.503(10) and 1.504(10) A. The third oxygen atom, showing a longer P-O distance (1.546(9) A), is not bonded to the metal center, nor is it bonded to a proton. The combined IR and NMR proton-phosphorus cross-polarization kinetic data together with the X-ray data confirm that the cadmium phosphonate has the zwitterionic structure (NH2(+)CH2P(O2Cd2)O-) similar to the initial aminophosphonic acid H4L.

Oxone, a cheap, stable, and nonhazardous oxidizing reagent, transforms α,β-unsaturated ketones of defined stereochemistry into their corresponding vinyl acetates through a Baeyer-Villiger reaction. This process is general and straightforward, tolerating a wide range of functional groups.

Alkali metal ion exchange on a-and -titanium phosphate is reported. In -titanium phosphate, Li+ and Na+ exchange in acidic solution but K+ and Cs+ do not. Phases of half and full exchange are formed. In the -titanium phosphate, Li+, Na+, K+, and Cs+ exchange in acidic solution. Phases of 25, 50, and 100% substitution are formed. The selectivity sequences are obtained from the study of binary systems, and their validity for polyionic systems is discussed. Free energy, enthalpy, and entropy of the exchange reactions are also presented. A mechanism of exchange is proposed.

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The reaction of zinc chloride with 1,2-ethanediylbis(iminomethylene)bis(phosphonic acid) in acidic conditions yielded dichloro[1,2-ethanediylbis(iminomethylene)bis(phosphonato)]trizinc dihydrate, Zn 3 Cl 2 (HO 3 PCH 2 NHCH 2 CH 2 NHCH 2 -PO 3 H) 2 ·2 H 2 O which crystallizes in the monoclinic system and space group P2 1 /n, with the unit cell parameters a = 9.94316(4), b = 10.44577(5), c = 24.3240(1) Å, β = 90.003(1)°, and Z = 4. The crystal structure was determined ab initio

trans-Cyclopropanamides were obtained, in high yield, from 2-chloro-3-hydroxyamides by a sequenced elimination-cyclopropanation process promoted by Samarium/diiodomethane or Samarium diiodide and Samarium/diiodomethane.