A method of synthesizing 7-silyl camptothecins and 7-silyl homocamptothecins includes the step of mixing a camptothecin or a homocamptothecin having hydrogen at the C7 position with a silyl radical generator and a silyl radical precursor under conditions to generate a silyl radical. SiR.sup.1 R.sup.2 R.sup.3 wherein R.sup.1, R.sup.2 and R.sup.3 are independently a C.sub.1-10 alkyl group, a C.sub.2-10 alkenyl group, a C.sub.2-10 alkynyl group, an aryl group, --(CH.sub.2).sub.m R.sup.11 or SiR.sup.12 R.sup.13 R.sup.14, wherein m is an integer within the range of 1 through 10 and R.sup.11 is a hydroxy group, an alkoxy group, an amino group, an alkylamino group, a dialkylamino group, F, Cl, a cyano group, --SR.sup.c or a nitro group, and wherein R.sup.12, R.sup.13 and R.sup.14 are independently the same or different an alkyl group or an aryl group.
Methods of enhancing the solubility of a fluorinated compound in an organic solvent are provided. In one embodiment, carbon dioxide gas pressure is applied to the solvent at a pressure effective to enhance the solubility of the fluorinated compound. The method may further include recrystallizing the fluorinated compound by reducing the pressure of the carbon dioxide gas. Also provided are methods of conducting a reaction using a fluorinated compound in an organic solvent. In one embodiment, the method comprises applying carbon dioxide pressure to an organic solvent comprising at least one substrate and a fluorinated catalyst, in an effective amount to solubilize the catalyst; and permitting the fluorinated catalyst to catalyze the reaction of the substrate to form a product. The catalyst is optionally separated from the reaction product and solvent after the reaction by the release of the pressure.
A method of synthesizing a compound having the formula: ##STR1## from a compound having the formula: ##STR2## wherein R.sup.1 is hydrogen, fluorine, chlorine or SiR.sup.5 R.sup.6 R.sup.7, wherein R.sup.5, R.sup.6, and R.sup.7 are independently the same or different an alkyl group or an aryl group, R.sup.2 is an alkyl group, R.sup.3 is a protecting group, R.sup.4 is an alkyl group, an allyl group, a propargyl group --CO.sub.2 H, or a benzyl group, R.sup.8 is --CO.sub.2 R.sup.10, wherein R.sup.10 is an alkyl group or an aryl group, X.sup.1 is OH and X.sup.2 is H, includes the step of exposing compound (III) to at least one of an organic acid or an inorganic acid. A compound has the general formula (III).
