Premium
Reaction of 1,1′‐Divinyl Ferrocene with One‐Electron Oxidants: Entry into Functionalised [4]Ferrocenophanes and Observation of an Isotope‐Dependent Chemoselectivity Effect
Author(s) -
Gleixner Renate M.,
Joly Kévin M.,
Tremayne MaryJane,
Kariuki Benson M.,
Male Louise,
Coe Diane M.,
Cox Liam R.
Publication year - 2010
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.200903478
Subject(s) - chemoselectivity , chemistry , ferrocene , carbamate , medicinal chemistry , kinetic isotope effect , stereoselectivity , deuterium , yield (engineering) , alcohol , electrochemistry , organic chemistry , catalysis , physics , materials science , electrode , quantum mechanics , metallurgy
1,1′‐Divinyl ferrocene ( 2 ) reacts with K 3 [Fe(CN) 6 ] under basic biphasic conditions to give a [4]ferrocenophane ( 4 ) in good yield. Incorporating deuterium labels into the internal positions of the vinyl groups of 2 affects the chemoselectivity of the reaction; thus under identical reaction conditions, [D 2 ]‐ 2 reacts to provide a diol‐functionalised [4]ferrocenophane, [D 2 ]‐ D / L ‐ 6 in addition to the expected keto‐alcohol, [D 1 ]‐ 4 . Variants on this one‐electron oxidative cyclisation methodology can be used to give other [4]ferrocenophanes; thus, the reaction of 2 with CuCl 2 in MeOH or i PrOH leads to dialkoxy [4]ferrocenophanes 19 and 20 , respectively, whereas the reaction of 2 with benzyl carbamate in the presence of t BuOCl gives a bis(carbamate)[4]ferrocenophane, 21 . Mechanisms to account for the formation of the products, the stereoselectivity, and the unusual isotope‐dependent chemoselectivity in the reaction of 2 and [D 2 ]‐ 2 with K 3 [Fe(CN) 6 ] are proposed.