Syntheses of homochiral 1,2-ferrocene-functionalized Lewis acids and acid/base pairs
摘要:
We report a facile approach for the synthesis of homochiral 1,2-disubstituted ferrocene-functionalized Lewis acids and acid/base pairs. The synthesis is based on chiral induction facilitated by the ortho sulfinyl subsitutent in S-Fc{S(O)p-tol}, S-1, to obtain the key intermediate S,S-p-1,2-fc{S(O)p-tol}(BMes(2)), S,S-p-2a (p-tol = C6H4Me-4, Mes = C6H2Me3-2,4,6). Subsequent substitution of the -S(O)p-tol substituent in S,S-p-2a gives access to a range of enantiomerically pure S-p-1,2-ferrocene-functionalized Lewis acids and acid/base pairs including the first homochiral 1-phosphino-2-borylferrocene. Enantiomeric excesses (e.e.s) of >95% have typically been achieved using this methodology. (C) 2011 Elsevier B.V. All rights reserved.
Syntheses and Anion Binding Capabilities of Bis(diarylboryl) Ferrocenes and Related Systems
作者:Michael J. Kelly、Alexander E.J. Broomsgrove、Ian R. Morgan、Inke Siewert、Philip Fitzpatrick、Jessica Smart、Dragoslav Vidovic、Simon Aldridge
DOI:10.1021/om400152x
日期:2013.5.13
Isomeric diborylated ferrocenes featuring 1,1′-, 1,2-, and 1,3-substitution patterns have been targeted via a combination of electrophilic aromatic substitution and directed ortho-lithiation protocols. While none of these systems are competent for the Lewis acid chelation of fluoride, related systems featuring a mixed B/Si acceptor set capture 1 equiv of fluoride via a Si–F–B bridging motif.