69503-11-3Relevant academic research and scientific papers
CHEMISTRY OF METALLACYCLOBUTANONES. PART 1. SYNTHESYS AND RING INVERSION OF SOME HYGHLY PUCKERED METALLACYCLOBUTAN-3-ONE (SLIPPED OXODIMETHYENEMETHANE) COMPLEXES OF PLATINUM; cRYSTAL STRUCTURE OF 2,4-BIS(METHOXYCARBONYL)-1,1-BIS(TRIPHENYLPHOSPHINE)PLATINACYCLOBUTAN-3-ONE MONOHYDRATE.
Clarke, David A.,Kemmitt, Raymond D. W.,Mazid, Muhammed A.,McKenna, Peter,Russel, David R.,et al.
, p. 1993 - 2002 (2007/10/02)
The reaction of the carbonato-complexes 3)L2> with esters of 3-oxopentanedioic acid, RCH2COCH2R, in warm ethanol afford, in high yield, the formally platinacyclobutan-3-one compounds (R=CO2Me, L=PPh3, AsPh3, PMePh2 or PMe2Ph; 2L=Ph2PCH2PPh2; R=CO2Et, L=PPh3, or ASPh3; R=CO2Prn, L=PPh3, or ASPh3).The compounds (R=CO2Me, L=PPh3, AsPh3, PMePh2, or PMe2Ph; R=CO2Et, L=PPh3 or AsPh3) are also formed upon treatment of benzene solutions of 4> with RCH2COCH2R in the presence of air.Using the latter method, the triphenylphosphine derivative is often contamined with the peroxo-ring compound which is the major product if the reaction is carried out in diethyl ether.The reaction of 2)(PPh3)2> with MeO2CCH2COCH2CO2Me in diethyl ether also gives the peroxo-ring compound.Treatment of MeO2CCH2COCH2CO2Me with either 3)2> in benzene in the presence of air, in ethanol, cis-2(PPh3)2> in ethanol, or cis-2(PPh3)2> and silver oxide in dichloromethane also affords .A single-crystal X-ray diffraction study has been carried out on (3a).The crystals are triclinic, space group P, Z=2, in a unit cell with a=17.59(1), b=12.736(6), c=10.27(1) Angstroem, α=118.2(1), β=94.7(1), and γ=74.0(1) deg.The structure has been refined to R 0.035 (R' 0.036) for 7 263 reflections with I >= 3?(I).It can be considered to be based either upon a highly puckered platina-cyclobutan-3-one ring with a weak transannular Pt-C bond of 2.416(5) Angstroem, or a slipped η3-oxodimethylenemethane compound.N.m.r. data (1H, 13C-, and 31P-) are reported and variable-temperature 1H n.m.r. data for the compounds (R=CO2Me, L=PPh3, or AsPh3) are interpreted in terms of inversion of the platinacyclobutane-3-one ring through a planar transition state.The magnitude of the platinum-195 coupling to the axial and equatorial ring hydrogens of the platinacyclobutan-3-one ring is dependent upon the orientation of the CH bonds with respect to the square planar platinum function and the magnitude of 3J(cis-PPtCH) are controlled by the dihedral angle.
