"Extreme" Ugi reactions with some complex α-amino acids

Organic Letters

Volumn 14, Issue 18, 2012, Pages 4970-4973

  Turner, Charles Dylan ^a   Ciufolini, Marco A ^a  

^a UNIVERSITY OF BRITISH COLUMBIA   (Canada)

Author keywords

[No Author keywords available]

Indexed keywords

ALDEHYDE; AMINO ACID; CARBOXYLIC ACID; TITANIUM; TITANIUM TETRACHLORIDE;

ARTICLE; CATALYSIS; CHEMICAL STRUCTURE; CHEMISTRY; STEREOISOMERISM;

ALDEHYDES; AMINO ACIDS; CARBOXYLIC ACIDS; CATALYSIS; MOLECULAR STRUCTURE; STEREOISOMERISM; TITANIUM;

EID: 84868235034     PISSN: 15237060     EISSN: 15237052     Source Type: Journal    
DOI: 10.1021/ol302379a     Document Type: Article

References (10)

1. Reviews: (a)Dömling, A. Chem. Rev. 2006, 106, 17.
2. (b) De Graaf, C.; Ruijter, E.; Orru, R. V. A. Chem. Soc. Rev. 2012, 41, 3969.
3. Godet, T.; Bonvin, Y.; Vincent, G.; Ciufolini, M. A. Org. Lett. 2004, 6, 3281.
4. Turner, C. D. Dissertation; University of Bristish Columbia, 2012.
5. Turner, C. D.; Ciufolini, M. A. Heterocycles 2012, 85, 85.
6. Evans, D. A.; Britton, T. C.; Dorow, R. L.; Dellaria, J. F., Jr. Tetrahedron 1988, 44, 5525.
7. (b) Evans, D. A.; Britton, T. C.; Ellman, J. A.; Dorow, R. L. J. Am. Chem. Soc. 1990, 112, 4011.
8. Compare: Ugi, I.; Demharter, A.; Hörl, W.; Schmid, T. Tetrahedron 1996, 52, 11657.
9. One may infer from the A-value of an NMe2 vs that of a CHMe2 (1.53 kcal/mol vs 2.52 kcal/mol: Eliel, E.; Wilen, S. H. Stereochemistry of Organic Compounds; Wiley: New York, NY, 1994; pp 696-697) that the steric demand of a CH-CH2OH branch is greater than that of an NMe unit. Therefore, a CH-CH2OH should provide more effective steric shielding of one of the imine faces than an NMe; i.e., it should promote higher diastereoselectivity. This is consistent with observation.
10. For instance, those found in the quinocarcin/bioxalomycin/ cyanocyclin family of cytotoxic natural products: Scott, J. D.; Williams, R. M. Chem. Rev. 2002, 102, 1669.