New application of microwave digestion-inductively coupled plasma-mass spectrometry for multi-element analysis in komatiites.

A new method using microwave digestion combined with inductively coupled plasma-mass spectrometry (ICP-MS) was studied to analyze the elemental composition of a variety of komatiites samples. Microwave digestion consisted in two-stage heating and pressurizing acid treatments for maximum dissolution of the samples. We report here different quality control measurements (external and internal calibration, monitoring of reference materials) which involve standard deviation calculations and recovery examinations in order to test the precision and accuracy of the analytical procedure.

Metal-templated diyne cyclodimerization and cyclotrimerization.

Reaction of [Pt(CH3)2(COD)] (COD = 1,5-cyclooctadiene) with Ph2PCCCCPPh2 led to a mixture of [{Pt(CH3)2}2(mu-Ph2PC4PPh2)2] (1) and [{Pt(CH3)2}3(mu-Ph2PC4PPh2)3] (2). Reaction of [PtCl2(COD)] with Ph2PCCCCPPh2 led to a mixture of the thermally unstable compounds [{PtCl2}2(mu-Ph2PC4PPh2)2] (3) and [{PtCl2}3(mu-Ph2PC4PPh2)3] (4) which transform into [{PtMe2}2{mu-C8(PPh2)4}] (5) and [{PtMe2}3{mu3-C12(PPh2)6}] (6) containing 8-membered diene-diyne and 12-membered triene-triyne rings, respectively. Compound 2 can be converted to [{PtMe2}3{C12(PPh2)6}] (7) by heating with CuCl at 80 degrees C, while 1 can be heated without significant cycloaddition.