Solvent-free tissue processing using supercritical carbon dioxide.

Aims: Xylene is most often employed in tissue processing protocols for paraffin embedding, but poses a health hazard. The aim of this study was to evaluate a solvent-free processing protocol that uses supercritical carbon dioxide (scCO(2) ) as an intermediate.

Methods And Results: A series of tests (with bovine tissues) was run, evaluating dehydration and tissue shrinkage in our new scCO(2) -based protocol as compared with routine processing using a graded ethanol and xylene series.

Carbenerhodium complexes of the half-sandwich-type: synthesis, substitution, and addition reactions.

A series of carbenerhodium(I) complexes of the general composition [(eta5-C5H5)Rh(=CRR')(L)] (2a-2i) with R = R'= aryl and L = SbiPr3 or PR3 has been prepared from the square-planar precursors trans-[RhCl(=CRR')(L)2] and NaC5H5 in excellent yields. Reaction of the triisopropylsibane derivative 2a. which contains a rather labile Rh-Sb bond, with CO, PMe3, and CNR (R = Me, CH2Ph, tBu) leads to the displacement of the SbiPr3 ligand and affords the substitution products [(eta5-C5H5)Rh(=CPh2)(L)] (3-7).