Abstract
The reaction of cholesterol with the antimony trichloride reagent was investigated in order to elucidate the coloration mechanism. Two reaction products, 3, 5-cholestadiene (I) and 3, 3'-bis (2, 4-cholestadiene) (II), were isolated from the colored solution. It was assumed that 2, 4-cholestadiene (IV) might be produced in the colored solution and IV should change to I during the process of the isolation. I and II were observed to color yellow and then red with the antimony trichloride reagent. It was concluded from the evidence obtained by electron spin resonance study on the colored solution that this coloration might be ascribed to cation-radical. The mechanism of the dimerization of IV to II was examined.
