Enhanced asymmetric induction in cycloadditions to bridgehead-chiral vinyl dioxazaborocines

Tetrahedron Letters

Volumn 41, Issue 21, 2000, Pages 4229-4233

  Davies, Christopher D ^a   Marsden, Stephen P ^a   Stokes, Elaine S E ^b  

^a IMPERIAL COLLEGE LONDON   (United Kingdom)

^b ASTRAZENECA   (United Kingdom)

Author keywords

Asymmetric synthesis; Boron and compounds; Cycloaddition; Isoxazolines; Nitrile oxides; Nitrones

Indexed keywords

BORON DERIVATIVE; ISOXAZOLINE DERIVATIVE; NITRILE; NITRONE; OXIDE;

ARTICLE; CHEMICAL STRUCTURE; CHIRALITY; PROTON NUCLEAR MAGNETIC RESONANCE; STEREOCHEMISTRY; SYNTHESIS;

EID: 0034729176     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(00)00571-2     Document Type: Article

References (13)

1. For example, chiral Lewis acids have been used to promote nitrone cycloadditions to oxazolidinone-substituted olefins (Jensen, K. B.; Gothelf, K. V.; Hazell, R. G.; Jørgensen, K. A. J. Org. Chem. 1997, 62, 2471-2477 and references cited therein) or enol ethers (Simonsen, K. B.; Bayón, P.; Hazell, R. G.; Gothelf, K. V.; Jørgensen, K. A. J. Am. Chem. Soc. 1999, 121, 3845-3853 and references cited therein), while chiral rhodium catalysts have been used to promote asymmetric cycloadditions of oxonium ylides. (Hodgson, D. M.; Stupple, P. A.; Johnstone, C. Chem. Commun. 1999, 2185-2186 and references cited therein).
2. For example, chiral Lewis acids have been used to promote nitrone cycloadditions to oxazolidinone-substituted olefins (Jensen, K. B.; Gothelf, K. V.; Hazell, R. G.; Jørgensen, K. A. J. Org. Chem. 1997, 62, 2471-2477 and references cited therein) or enol ethers (Simonsen, K. B.; Bayón, P.; Hazell, R. G.; Gothelf, K. V.; Jørgensen, K. A. J. Am. Chem. Soc. 1999, 121, 3845-3853 and references cited therein), while chiral rhodium catalysts have been used to promote asymmetric cycloadditions of oxonium ylides. (Hodgson, D. M.; Stupple, P. A.; Johnstone, C. Chem. Commun. 1999, 2185-2186 and references cited therein).
3. For example, chiral Lewis acids have been used to promote nitrone cycloadditions to oxazolidinone-substituted olefins (Jensen, K. B.; Gothelf, K. V.; Hazell, R. G.; Jørgensen, K. A. J. Org. Chem. 1997, 62, 2471-2477 and references cited therein) or enol ethers (Simonsen, K. B.; Bayón, P.; Hazell, R. G.; Gothelf, K. V.; Jørgensen, K. A. J. Am. Chem. Soc. 1999, 121, 3845-3853 and references cited therein), while chiral rhodium catalysts have been used to promote asymmetric cycloadditions of oxonium ylides. (Hodgson, D. M.; Stupple, P. A.; Johnstone, C. Chem. Commun. 1999, 2185-2186 and references cited therein).
4. (a) Yoshida, Y.; Ukaji, Y.; Fujinami, S.; Inomata, K. Chem. Lett. 1998, 1023-1024;
5. (b) Shimizu, M.; Ukaji, Y.; Inomata, K. Chem. Lett. 1996, 455-456; Ukaji, Y.; Sada, K.; Inomata, K. Chem. Lett. 1993, 1847-1850.
6. (b) Shimizu, M.; Ukaji, Y.; Inomata, K. Chem. Lett. 1996, 455-456; Ukaji, Y.; Sada, K.; Inomata, K. Chem. Lett. 1993, 1847-1850.
7. Gothelf, K. V.; Jørgensen, K. A. Chem. Rev. 1998, 98, 863-909.
8. Davies, C. D.; Marsden, S. P.; Stokes, E. S. E. Tetrahedron Lett. 1998, 39, 8513-8516.
9. Owing to the availability to us of only a single enantiomer of 2-aminoindan, amine 3g was in fact prepared from (R)-aminoindan and (S)-styrene oxide-the enantiomeric structure is shown in the paper for ease of comparison of data.
10. Martinez-Fresneda, P.; Vaultier, M. Tetrahedron Lett. 1989, 30, 2929-2932.
11. 1H NMR spectrum recorded at 400 MHz. We thank Mr. Dick Sheppard and Mr. Paul Hammerton of this department and Mr. Rob Horton of AstraZeneca for running these experiments.
12. Compound 3h was prepared from (S)-α-methylbenzylamine and (S)-propylene oxide; the enantiomeric structure is shown here for clarity. Compound 3i was prepared from (R)-α-methylbenzylamine and ethylene oxide. Compound 3j was prepared by condensation of (R)-α-methylbenzylamine with two equivalents of ethyl bromoacetate followed by exposure to excess methylmagnesium bromide.
13. Farthing, C. N.; Marsden, S. P. Tetrahedron Lett. 2000, 41, 4235-4238.