Hydrochloric Acid → HCID 131724884, compound

Participants

Reaction Steps

Trifluoromethanol-tetraphenylporphyrin (22) was synthesized according to a modification of the procedure reported by Prakash and Olah (J. Am. Chem. Soc. 1989, 111, 393). All flasks and syringes were flame-dried and cooled under argon. To a stirring solution of formyl-tetraphenylporphyrin (21) (25 mgs, 0.039 mmol) in distilled tetrahydrofuran (15 mL) was added TMS-CF3 (1.16 μL, 0.585 mmol). The mixture was cooled to 0° under argon, and a catalytic amount of TBAF (10 μL, 0.01 mmol) was added. The reaction was monitored by TLC whereby disappearance of the green starting material (Rf=0.5) and appearance of the reddish, faster moving trifluoromethylated siloxy intermediate (Rf=0.78) signaled completion of the reaction. Hydrolysis was achieved by addition of 0.5M hydrochloric acid (until the solution takes on a bright green colour). Methylene chloride and a solution of saturated sodium acetate were then added to neutralize the product. The organic layer was separated, the solvent removed in vacuo, and the residue chromatographed on silica gel 60, 70-230 mesh, (50-100% CH2Cl2/hexanes as gradient eluent) to yield 24.7 mgs (89%) of trifaoromethanol-tetraphenylporphyrin. One faint impurity was visible by TLC, a light green spot (Rf=0.73), but did not impede isolation of the desired product (Rf=0.34) which moved much slower.

Provenance & Evidence