ORGLIST: 1-Carboxy-2-amino-cyclopropanes.

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From: Jonas Nilsson (jonni$##$ifm.liu.se)
Date: Wed May 02 2001 - 09:54:20 EDT


Dear Readers.
I'm having trouble converting the dimethyl 1R,2R-cyclopropanedicarboxylate
to the methyl 1R-amino-2R-cyclopropanecarboxylate.

|> = cyclopropane

MeOOC-|>-COOMe -> MeOOC-|>-COOH This works fine!
MeOOC-|>-COOH -> MeOOC-|>-CNO (Using DPPA / Et3N) No
problems here!
MeOOC-|>-CNO -> MeOOC-|>-NHCOOR Works nice with any
alcohol I've tried

Now to the hard part:
MeOOC-|>-CNO -> MeOOC-|>-NH3+ (Using HCl(aq or MeOH))
Doesn't work
MeOOC-|>-CNO -> MeOOC-|>-NH2 (Using H2O) Doesn't work
MeOOC-|>-NHCOOR -> MeOOC-|>-NH2 (Different deprotection
strategies) Doesn't work

I've used different carbamates (FMOC, BOC, CBZ, Me, Ph) and different
deprotection strategies, but all seem to fail. It's hard for me to conclude
what happens, but I think the ring breaks up.

I've searched the crossfire database for reactions, and there are a lot of
compounds with a 1-carbonyl-2-(NH-prot.group.) substituted ring. There are
also a lot of reactions invovling 1-(free amine) and a 2-aryl/alkyl
substituent pattern. But I get no hits with 1-(free amine) 2-(electron
withdrawing group). Are these compounds impossible to make or what?

I later on need to derivitize both amine and carboxylate as amide bonds.
Will I have to do something like this do you think?

MeOOC-|>-NHCOOR (DIBAL)-> HOCH2-|>-NHCOOR (Deprot, coupling)->
HOCH2-|>-NHCOR' (ox., coupling) -> R''NOC-|>-NHCOR'

Any other suggestions?
Please advise.
/jN
--

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      Jonas Nilsson
IFM, Dept. of Chemistry
  Linkoping University
    581 83 Linkoping
           Sweden

 phone: +46-13-285690
 fax: +46-13-281399
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