Ammonium-directed oxidation of cyclic allylic and homoallylic amines.
The ammonium-directed olefinic oxidation of a range of cyclic allylic and homoallylic amines has been investigated. Functionalization of a range of allylic 3-(N,N-dibenzylamino)cycloalk-1-enes with m-CPBA in the presence of Cl(3)CCO(2)H gives exclusively the corresponding syn-epoxide for the 5-membered ring (>99:1 dr), the anti-epoxide for the 8-membered ring (>99:1 dr), and predominantly the anti-epoxide for the 7-membered ring (94:6 dr). Oxidation of the homoallylic amines 3-(N-benzylamino)methylcyclohex-1-ene and 3-(N,N-dibenzylamino)methylcyclohex-1-ene gave, in both cases, the corresponding N-protected 1,2-anti-2,3-syn-3-aminomethylcyclohexane-1,2-diol with high levels of diastereoselectivity (>or=90:10 dr). The versatile synthetic intermediates resulting from these oxidation reactions are readily transformed into a range of amino diols.
Bond
Christopher W
CW
Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK.
Cresswell
Alexander J
AJ
Davies
Stephen G
SG
Fletcher
Ai M
AM
Kurosawa
Wataru
W
Lee
James A
JA
Roberts
Paul M
PM
Russell
Angela J
AJ
Smith
Andrew D
AD
Thomson
James E
JE