REDOX-RESPONSIVE SURFACTANTS - SYNTHESIS OF 1,1-DIFERROCENYL-N-ALKANES (C-1, C-5, C-7, C-19) VIA REACTION OF (DIFERROCENYL) METHYL CARBOCATION WITH CARBANIONS
B. Bildstein et al., REDOX-RESPONSIVE SURFACTANTS - SYNTHESIS OF 1,1-DIFERROCENYL-N-ALKANES (C-1, C-5, C-7, C-19) VIA REACTION OF (DIFERROCENYL) METHYL CARBOCATION WITH CARBANIONS, Journal of organometallic chemistry, 496(2), 1995, pp. 175-186
Diferrocenylmethylium cation with chloride or tetraphenylborate as cou
nter-ion is prepared from diferrocenylmethanol by dehydration with str
ong acids. Treatment with trimethylchrorosilane removes residual water
to afford anhydrous methylium salts, which are highly reactive electr
ophiles for alkylation of group 14 (carbanions), group 15 (amines), gr
oup 16 (alkoxides), and, remarkably, group 17 (fluoride) nucleophiles.
Reaction with long-chain carbanions yields 1,1-diferrocenyl substitut
ed n-alkanes, which are of potential interest as redox-responsive surf
actants. Single crystal structure analyses reveal a tendency for ambip
hilic behavior to increase with increasing chain length. Medium chain
length 1,1-diferrocenyl-n-alkanes show the expected intermolecular sta
cking, whereas for the longest n-alkane synthesized, 1,1-diferrocenyl-
n-nonadecane, intermolecular complexation with n-octadecane is observe
d.