Asymmetric Lewis acid catalyzed addition of isocyanides to aldehydes. Synthesis of 5-amino-2-(1-hydroxyalkyl)oxazoles

Stannous chloride efficiently catalyzes condensations between alpha -isocyanoacetamides C==NCHRCOR1 (I, R = H, PhCH2; R1 = N-morpholinyl, Et2N) and a variety of aldehydes to afford the corresponding 5-amino-2-(1-hydroxyalkyl)oxazoles II (R2 = Et, n-C6H13, Me2CH, cyclohexyl, tert-Bu, COOEt, Ph, etc.) in good to excellent yields. The [Sn-(R)-Ph-PyBox](OTf)2-catalyzed reaction between I (R = PhCH2; R1 = N-morpholinyl) and 2-(benzyloxy)acetaldehyde shows an isoinversion effect, with the max. enantiomeric excess of oxazole II (R2 = PhCH2OCH2) (80%) obtained at -40 Deg. [on SciFinder (R)]


Published in:
European Journal of Organic Chemistry, 24, 4076-4080
Year:
2007
Keywords:
Stereoselective synthesis (Lewis acid-catalyzed prepn. of 5-amino-2-(1-hydroxyalkyl)oxazoles by condensation of alpha -isocyanoacetamides with aldehydes and extension to asym. Passerini-type addn. using [Sn-(R)-Ph-PyBox](OTf)2 catalyst); Aldehydes; Isocyanides Role: RCT (Reactant) ; RACT (Reactant or reagent) (Lewis acid-catalyzed prepn. of 5-amino-2-(1-hydroxyalkyl)oxazoles by condensation of alpha -isocyanoacetamides with aldehydes and extension to asym. Passerini-type addn. using [Sn-(R)-Ph-PyBox](OTf)2 catalyst); Cyclocondensation reaction; Cyclocondensation reaction catalysts (Passerini-type; Lewis acid-catalyzed prepn. of 5-amino-2-(1-hydroxyalkyl)oxazoles by condensation of alpha -isocyanoacetamides with aldehydes and extension to asym. Passerini-type addn. using [Sn-(R)-Ph-PyBox](OTf)2 catalyst); Cyclocondensation reaction catalysts (stereoselective Passerini-type; Lewis acid-catalyzed prepn. of 5-amino-2-(1-hydroxyalkyl)oxazoles by condensation of alpha -isocyanoacetamides with aldehydes and extension to asym. Passerini-type addn. using [Sn-(R)-Ph-PyBox](OTf)2 catalyst); Cyclocondensation reaction (stereoselective ; Passerini-type; Lewis acid-catalyzed prepn. of 5-amino-2-(1-hydroxyalkyl)oxazoles by condensation of alpha -isocyanoacetamides with aldehydes and extension to asym. Passerini-type addn. using [Sn-(R)-Ph-PyBox](OTf)2 catalyst) ; isocyanoacetamide aldehyde tin addn Passerini asym; enantioselective Passerini cyclocondensation tin chiral bidentate ligand; oxazole amino prepn stannous chloride catalyst; aminooxazole prepn stannous chloride catalyst
Note:
CAN 147:486361
28-6
Heterocyclic Compounds (More Than One Hetero Atom)
National Laboratory for Molecular Sciences, Laboratory of Chemical Biology, Institute of Chemistry,Chinese Academy of Sciences,Beijing,Peop. Rep. China.
Journal
1434-193X
written in English.
7772-99-8 (Stannous chloride); 62086-04-8 (Tin(II) triflate); 128249-70-7 Role: CAT (Catalyst use), USES (Uses) (Lewis acid-catalyzed prepn. of 5-amino-2-(1-hydroxyalkyl)oxazoles by condensation of alpha -isocyanoacetamides with aldehydes and extension to asym. Passerini-type addn. using [Sn-(R)-Ph-PyBox](OTf)2 catalyst); 78-84-2 (Isobutanal); 100-52-7 (Benzaldehyde); 104-87-0 (4-Methylbenzaldehyde); 104-88-1 (4-Chlorobenzaldehyde); 111-71-7 (Heptanal); 122-78-1 (Benzeneacetaldehyde); 123-38-6 (1-Propanal); 135-02-4 (2-Methoxybenzaldehyde); 555-16-8 (4-Nitrobenzaldehyde); 630-19-3 (2,2-Dimethylpropanal); 924-44-7; 2043-61-0 (Cyclohexanecarboxaldehyde); 3132-99-8 (3-Bromobenzaldehyde); 60656-87-3 (Benzyloxyacetaldehyde); 67434-29-1; 85059-48-9; 500555-97-5; 845791-23-3 Role: RCT (Reactant), RACT (Reactant or reagent) (Lewis acid-catalyzed prepn. of 5-amino-2-(1-hydroxyalkyl)oxazoles by condensation of alpha -isocyanoacetamides with aldehydes and extension to asym. Passerini-type addn. using [Sn-(R)-Ph-PyBox](OTf)2 catalyst); 728041-22-3P; 728041-24-5P; 728041-25-6P; 728041-26-7P; 728041-28-9P; 728041-29-0P; 728041-31-4P; 952683-22-6P; 952683-23-7P; 952683-24-8P; 952683-25-9P; 952683-26-0P; 952683-27-1P; 952683-28-2P; 952683-29-3P; 952683-30-6P; 952683-31-7P; 952683-32-8P Role: SPN (Synthetic preparation), PREP (Preparation) (Lewis acid-catalyzed prepn. of 5-amino-2-(1-hydroxyalkyl)oxazoles by condensation of alpha -isocyanoacetamides with aldehydes and extension to asym. Passerini-type addn. using [Sn-(R)-Ph-PyBox](OTf)2 catalyst)
Laboratories:




 Record created 2010-11-25, last modified 2018-03-17


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