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Raphael J F Berger

Publications and source records attributed to Raphael J F Berger.

4 recordsLinked to original sources
PubMed2006

Expectation and surprise in group 13 organometallics: molecular vs. polymeric aggregation of Me2Ga and Me2In norcamphor oximates.

Whereas (meso)-[(norcamphor oximato)GaMe2]2 exhibits the dimeric M2O2N2 motif favoured by organo group 13 metal oximates, the Me2In derivative [{(meso)-[(norcamphor oximato)InMe2]2}2]infinity aggregates distinctly different with the In atoms adopting coordination number (CN)=5; compound is the first oximato-based chain-like coordination polymer in group 13 organometallics; it comprises alternating M2O2N2 and M2O2 ring dimers interconnected via two types of a fifth dative bond (O-->In and N-->In) to yield the new {M4O4N4}infinity motif; the calculated energetics of the heteroatom rings involved in and confirm the diverging aggregational behaviour of Ga and In.

Journal Article↗
PubMed2006

First mixed hydrazide/hydroxylamide metal aggregates.

The first organometallic clusters of mixed hydrazide/hydroxylamide clusters of zinc, [Zn(MeZn)(4)(HNNMe(2))(2)(ONEt(2))(4)] and {Zn(EtZn)(4)[HNN(CH(2))(5)](2)(ONEt(2))(4)} were synthesized in one-pot synthesis protocols from dialkylzinc solutions, substituted hydrazines and N,N-diethylhydroxylamine; competing for the Zn atoms, the different binding properties of hydrazide and hydroxylamide ligands in these heteroleptic clusters are discussed.

Journal Article↗
PubMed2005

Isomeric mono- and bis[(phosphane)gold(I)] thiocyanate complexes.

The solid-state IR spectrum of Me(3)PAuSCN shows two signals in the range of the C-N stretching vibrations at 2075 and 2113 cm(-1). On the basis of thoroughly tested quantum chemical ab initio calculations (MP2 level of theory) these signals have been assigned to the two isomeric forms Me(3)PAuNCS and Me(3)PAuSCN. The molecular structures, the vibrational frequencies, and the relative energies of the two species have been calculated and the results compared with the experimental IR data. Treatment of Me(3)PAuSCN with equimolar quantities of [(Me(3)P)Au](+)[SbF(6)](-) in CH(2)Cl(2) at -78 degrees C gives the dinuclear reaction product [C(7)H(9)Au(2)NP(2)S](+)[SbF(6)](-) in high yields. A comparison of results of ab initio calculations and IR data suggest that at least three isomeric cationic species [(R(3)PAu)(2)NCS](+), [(R(3)PAu)(2)SCN](+) and [(R(3)PAu)SCN(AuPR(3))](+) are present, the second and third being the predominant components. The structures and vibrational frequencies of all three species have been calculated. The relative energies in the gas phase and in solution are discussed and compared with the corresponding data of the experimental IR spectra.

Crystallography, X-Ray↗