Catalytic efficiency, ligand acceleration, and concentration effect in magnesium ion mediated 1,3-dipolar cycloadditions of mesitonitrile oxide to allylic alcohols

Tetrahedron Letters

Volumn 38, Issue 23, 1997, Pages 4095-4098

  Kanemasa, Shuji ^a   Okuda, Kumi ^a   Yamamoto, Hidetoshi ^b   Kaga, Shinsuke ^a  

^a KYUSHU UNIVERSITY   (Japan)

^b YAMAGUCHI UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

ALLYL ALCOHOL; LIGAND; MAGNESIUM ION; NITRILE;

ARTICLE; CATALYSIS; CHEMICAL REACTION; DRUG SYNTHESIS; STEREOCHEMISTRY;

EID: 0030908679     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(97)00834-4     Document Type: Article

References (10)

1. (a) Kanemasa, S.; Nishiuchi, M.; Kamimura, A.; Hori, K. J. Am. Chem. Soc. 1994, 116, 2324-2339.
2. (b) Kanemasa, S.; Nishiuchi, M.; Wada, E. Tetrahedron Lett. 1992, 33, 1357-1360.
3. (c) Kanemasa, S.; Kobayashi, S.; Nishiuchi, M.; Yamamoto, H.; Wada, E. Tetrahedron Lett. 1991, 32, 6367-6370.
4. Zinc ion catalyzed stereocontrol of nitrile oxide cycloadditions are known: Ukaji, Y.; Sada, K.; Inomata, K. Chemistry Lett. 1993, 1847-1850.
5. Kanemasa, S.; Nishiuchi, M. Tetrahedron Lett. 1993, 34, 4011-4014.
6. No rate acceleration of cycloadditions of benzonitrile oxide with allylic alcohols has been reported in our previous work (Ref. 1a).
7. This concentration effect is based on the quick equilibrating formation of three component complex between 1, magnesium ion, and 2a. Although the concentration of complex becomes lower in a diluted solution, the rate of cycloaddition should hold its inherent rate.
8. Coordination of ligand 5 to the magnesium ion can be confirmed by the rate acceleration observed in the reaction of 1 with 6 and norbornene in the presence of magnesium ion.
9. Preliminary study including the reaction of 1 with the magnesium alkoxide of 2a in the presence of nonracemic 5 (1 equiv) has shown only a poor chiral induction. Structural design of ligand accelerators is needed.
10. Zinc catalyzed asymmetric nitrile oxide cycloaddition was reported recently: Shimizu, M.; Ukaji, Y.; Inomata, K. Chemistry Lett. 1996, 455-456.