D. Vichard et al., SYNTHESIS, X-RAY STRUCTURE AND CHEMICAL-PROPERTIES OF 17-ALPHA-FERROCENYLESTRADIOL, Journal of organometallic chemistry, 484(1-2), 1994, pp. 1-8
The X-ray structure of 17 alpha-ferrocenylestradiol 1a shows that the
ferrocenyl group is at the alpha position of the steroid, below the pl
ane of the D ring. From acidic medium it is possible to obtain and iso
late the derivative with a carbenium ion in 17-alpha position. This io
n is transformed by various nucleophiles into the corresponding olefin
3 with -C=C- at the C16-C17 position. With NaBH4 in acidic medium the
reduction leads to a mixture of 17 alpha- and 17 beta-ferrocenyl C19H
26O 4a, 4b with a predominance of the beta product, owing to a more fa
vourable entrance of hydride in the alpha position. The oxidized deriv
ative 17 alpha-ferriciniumyl-estradiol tetrafluoroborate 5 was prepare
d and its are properties described.