The kinetics of ligand substitution for CO in Co4(CO)10(mu4-PPh2) , 1, have been investigated for the ligands P(OMe)3, P(OEt)3, PPh2H, P(0-i-Pr)3, P(n-Bu)3, PPh3, P(i-Pr)3, and PCy3 over a wide temperature range.

Trapping reactions, matrix isolation and kinetics of a few photogenerated silylenes and silenes have been studied. Several vinylsiliranes, the long sought intermediates from the addition of dimesitylsilylene to various 1,3-dienes, have been made and characterized. The product study by various nmr techniques demonstrates that the silylene addition to the dienes is highly stereospecific and the addition to the cis v bond is about 9 times faster than to the trans one in gis,trans-2,4-hexadiene. High stereospecifity of the addition of dimesitylsilylene to cis and trans-2-pentenes and to cis and trans-4-octenes has also been found. The reinvestigation of dimesitylsilylene to cis and t;rans-2-butene affords the possible explanation for the confusing results and wrong conclusion from the earlier report by Ando and coworkers.

Small weight percentages of certain high-molecular weight polymers added to liquids in turbulent flow through conduits can result in dramatic friction reduction. Although many current and potential uses of the drag reduction phenomenon exist, there is a fundamental problem: drag reduction efficacy decreases rapidly with flow time due to the mechanical degradation in flow of the added polymer. In this thesis study, dilute aqueous solutions of polyacrylamide were tested under turbulent flow conditions in an attempt to determine where mechanical degradation in flow occurs.