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Notes that the mentally ill and the courts would benefit immeasurably if the behavioral sciences would turn their attention to the task of empirically defining two words: dangerous and treatment. (Author/AM)

Two coordination polymers [MII(H2O)2]2[MoIV(CN)8]·4H2O [MII = Co (1), Mn (2)] were prepared as monocrystals and structurally characterised. These compounds crystallise in the tetragonal systems I4/m (1) and I4/mcm (2) and form three-dimensional networks containing channels occupied by two types of water molecules, i.e. coordinated to MII and crystallised ones. The dehydration of these materials occurs topochemically to give [MII(H2O)]2[MoIV(CN)8] compounds having an open metal coordination site on the MII ions that may be accessible to coordination by other species and serve as a reaction site. The intercalation of water, ammonia and amines has been studied. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

(Z)-CH3OCHCHC⋮CSi(OCH3)3 (2), ((Z)-CH3OCHCHC⋮C)2Si(OCH3)2 (5), and (Z)-CH3OCHCHC⋮CSi(OCH(CH3)2)3 (16) have been synthesized from (Z)-CH3OCHCHC⋮CH (1). Enynes 2 and 16 were subjected to a deprotonat...

A synthetic route to silicon-based composite ceramics that employs organosilicon polymer/metal oxide precursors is described. The precursor materials were obtained by dispersing metal oxides in the poly[(silylene)diacetylenes] 1. Subsequent pyrolysis of the dispersions above 1400 °C under various experimental conditions afforded β-SiC-based metal carbides and metal nitrides, metal silicides and Si3N4-based composites of defined compositions, in high ceramic yields. Under atmospheres of argon or of nitrogen, the precursor-to-ceramic conversion involved two critical transformations: i) the thermal cross-linking of 1 leading to an irreversible encapsulation of the oxide particle inside the polymeric matrix and ii) the carbothermal reduction of the oxide constituents by the carbon resulting from the degradation of polymer 1 to produce either the final carbide or the final nitride under the pyrolysis conditions. Moreover, it is shown that the encapsulation of the oxide particles inside a reactive matrix led to the formation of particle-tailored micro-scale reactors in which the reduction process took place with high efficiency.

An organometallic non-aqueous route to zinc phosphonates and to their intercalates has been studied. Various phosphonic acids react with dimethylzinc in THF media to afford the corresponding layered zinc phosphonates Zn(O 3 PR 1 ) (R 1 = Me, Ph, 2- and 3-thienyl, thiophen-3-ylmethyl) with evolution of methane. The presence of a primary n-alkylamine in the reaction mixture allows the one-pot formation of 2D-layered intercalated phases of general formula Zn(O 3 PR 1 )·RNH 2 [R 2 = Bu n , Pen n (= n-pentyl)] whereas a more bulky amine such as cyclohexylamine (Hex c NH 2 ) lead to the formation of 1D polymeric chains of formula Zn(O 3 PPh)·2Hex c NH 2 .

Pentacoordinate hydridosilicates [HSi(OR) 4 ] − (where R=Me, Et, n-Bu, i-Pr, Ph) as their K + salts are obtained from reactions of trialkoxy- (or phenoxy-) silanes with the respective alkoxide (or phenoxide). Compared to HSi(OEt) 3 , [HSi(OEt) 4 ]K exhibits a wide range of reactivities

Pentacoordinate hydridosilicates [HSi(OR) 4 ] − (where R=Me, Et, n-Bu, i-Pr, Ph) as their K + salts are obtained from reactions of trialkoxy- (or phenoxy-) silanes with the respective alkoxide (or phenoxide). Compared to HSi(OEt) 3 , [HSi(OEt) 4 ]K exhibits a wide range of reactivities

Synthese des complexes Ph 3 Si(OMe) 2 − K + (18-crown-6), Ph 2 Si(OMe) 3 K + (18-crown-6), Ph 3 SiF 2 − K + (18-crown-6) et MePhSiF 3 − K + (18-crown-6) a partir de K.F (18-crown-6) et de Ph 3 SiF ou MePhSiF 2 , de KOMe (18-crown-6) et de Ph n Si(OMe) 4-n (n=1, 2 ou 3). Etude de la reactivite de ces complexes vis-a-vis de nucleophiles (RMgX, RLi, ROLi, LiAlH 4 )

Two coordination polymers [MII(H2O)2]2[MoIV(CN)8]·4H2O [MII = Co (1), Mn (2)] were prepared as monocrystals and structurally characterised. These compounds crystallise in the tetragonal systems I4/m (1) and I4/mcm (2) and form three-dimensional networks containing channels occupied by two types of water molecules, i.e. coordinated to MII and crystallised ones. The dehydration of these materials occurs topochemically to give [MII(H2O)]2[MoIV(CN)8] compounds having an open metal coordination site on the MII ions that may be accessible to coordination by other species and serve as a reaction site. The intercalation of water, ammonia and amines has been studied. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)