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DOI: 10.1055/s-0029-1216963
Synthesis of a Conformationally Rigid Analogue of 2-Aminoadipic Acid Containing an 8-Azabicyclo[3.2.1]octane Skeleton
Publication History
Publication Date:
21 August 2009 (online)
Abstract
A new, conformationally rigid analogue of 2-aminoadipic acid, 8-[(benzyloxy)carbonyl]-3-methylene-8-azabicyclo[3.2.1]octane-1,5-dicarboxylic acid, is synthesized from dimethyl rac-2,5-dibromohexanedioate. The key steps involve alkylation-cyclization of 1-benzyl 2,5-dimethyl pyrrolidine-1,2,5-tricarboxylate with 3-chloro-2-(chloromethyl)prop-1-ene to yield the 8-azabicyclo[3.2.1]octane skeleton.
Key words
conformational restriction - bicyclic compounds - pyrrolidines - alkylations - cyclization
- 1
Hassian S.Auzzas L. Acc. Chem. Res. 2008, 41: 1241 -
2a
Hanessian S.McNaughton-Smith G.Lombart H.-G.Lubell WD. Tetrahedron 1997, 53: 12789 -
2b
Cativiela C.Díaz-de-Villegas MD. Tetrahedron: Asymmetry 2000, 11: 645 -
2c
Cativiela C.Díaz-de-Villegas MD. Tetrahedron: Asymmetry 1998, 9: 3517 -
2d
Park K.-H.Kurth MJ. Tetrahedron 2002, 58: 8629 -
2e
Cativiela C.Díaz-de-Villegas MD. Tetrahedron: Asymmetry 2007, 18: 569 -
3a
Biscoe TJ.Evans RH.Francis AA.Martin MR.Watkins JC.Davies J.Dray A. Nature 1977, 270: 743 -
3b
McLennan H.Hall JG. Brain Res. 1978, 149: 541 -
3c
Lodge D.Headley PM.Curtis DR. Brain Res. 1978, 152: 603 - 4
Kubyshkin VS.Mykhailiuk PK.Komarov IV. Tetrahedron Lett. 2007, 48: 4061 - 5 Dimethyl meso-2,5-dibromohexanedioate 5a was obtained using an identical procedure
to that described for diethyl meso-2,5-dibromohexanedioate,
see:
Guha PC.Sankaran DK. Org. Synth. 1955, 3: 623 - 6 Three diastereomers of 4: meso-, (2R,5R)- and
(2S,5S)- are formed
during the synthesis, each being suitable for alkylation. We chose
the crystalline (2R,5R)-isomer 4, which was easily separated from the
reaction mixture as it crystallizes upon standing in a fridge; the
product was filtered off and was washed with hexane. For the original procedure,
see:
Yamamoto Y.Hoshino J.Fujimoto Y.Ohmoto J.Sawada S. Synthesis 1993, 298 -
8a
Romesberg FE.Collum DB. J. Am. Chem. Soc. 1994, 116: 9198 -
8b
Ferey V.Vedrenne P.Toupet L.Le Gall T.Mioskowski C. J. Org. Chem. 1996, 61: 7244 - 10
Xu Y.-z.Choi J.Calaza MI.Turner S.Rapoport H. J. Org. Chem. 1999, 64: 4069 - 11
Einhorn J.Einhorn C.Ratajczak F.Pierre J.-L. Synth. Commun. 2000, 30: 1837 - 12
Masschelein KGR.Stevens CV.Dieltiens N.Claeys DD. Tetrahedron 2007, 63: 4712
References
The configurations at C-2 and C-5 in compounds 6, 9, 12a,b, 14 and 15a,b were not determined since they are lost upon subsequent transformation into the non-chiral 8-azabicy-clo[3.2.1]octane skeleton.
9The conversion without addition of HMPA was only 15% after 12 h at 20 ˚C. After 160 h, the transformation was complete; however, in the ¹H NMR spectrum of the crude mixture, together with 6, a number of unidentified side products were detected. All subsequent alkylations were performed in the presence of HMPA.