The catalytic diastereo- and enantioselective claisen rearrangement of 2-alkoxycarbonyl-substituted allyl vinyl ether

Advanced Synthesis and Catalysis

Volumn 346, Issue 11, 2004, Pages 1281-1294

  Abraham, Lars ^a   Körner, Marleen ^a   Schwab, Pia ^a   Hiersemann, Martin ^a  

^a DRESDEN UNIVERSITY OF TECHNOLOGY   (Germany)

Author keywords

keto ester; Allyl vinyl ether; Asymmetric catalysis; Claisen rearrangement; Lewis acids; Sigmatropic rearrangement

Indexed keywords

CARBONYL DERIVATIVE; COPPER DERIVATIVE; ETHER DERIVATIVE; LEWIS ACID; OXAZOLINE DERIVATIVE; VINYL DERIVATIVE;

ARTICLE; CATALYSIS; CATALYST; CHEMICAL BOND; CHEMICAL REACTION; CHEMICAL STRUCTURE; CLAISEN REARRANGEMENT; ENANTIOSELECTIVITY; REACTION ANALYSIS; STEREOCHEMISTRY; SUBSTITUTION REACTION;

EID: 7044286189     PISSN: 16154150     EISSN: None     Source Type: Journal    
DOI: 10.1002/adsc.200404051     Document Type: Article

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160. Replacing the benzyl ether by the 4-methoxybenzyl ether led to extensive decomposition of the corresponding allyl vinyl ether in the presence of the Lewis acid 1d. OPMB-ethers are know to be cleavable by Lewis acids, see: a) J. Wennerberg, L. Eklund, M. Polla, T. Frejd, J. Chem. Soc. Chem. Commun. 1997, 445; b) J. Wennerberg, C. Olofsson, T. Frejd, J. Org. Chem. 1998, 63, 359 5-3598; c) J. Wennerberg, F. Ek, A. Hansson, T. Frejd, J. Org. Chem. 1999, 64, 54-59; d) G. V. M. Sharma, C. G. Reddy, P. R. Krishna, J. Org. Chem. 2003, 68, 4574-4575.
161. Replacing the benzyl ether by the 4-methoxybenzyl ether led to extensive decomposition of the corresponding allyl vinyl ether in the presence of the Lewis acid 1d. OPMB-ethers are know to be cleavable by Lewis acids, see: a) J. Wennerberg, L. Eklund, M. Polla, T. Frejd, J. Chem. Soc. Chem. Commun. 1997, 445; b) J. Wennerberg, C. Olofsson, T. Frejd, J. Org. Chem. 1998, 63, 359 5-3598; c) J. Wennerberg, F. Ek, A. Hansson, T. Frejd, J. Org. Chem. 1999, 64, 54-59; d) G. V. M. Sharma, C. G. Reddy, P. R. Krishna, J. Org. Chem. 2003, 68, 4574-4575.
162. Replacing the benzyl ether by the 4-methoxybenzyl ether led to extensive decomposition of the corresponding allyl vinyl ether in the presence of the Lewis acid 1d. OPMB-ethers are know to be cleavable by Lewis acids, see: a) J. Wennerberg, L. Eklund, M. Polla, T. Frejd, J. Chem. Soc. Chem. Commun. 1997, 445; b) J. Wennerberg, C. Olofsson, T. Frejd, J. Org. Chem. 1998, 63, 359 5-3598; c) J. Wennerberg, F. Ek, A. Hansson, T. Frejd, J. Org. Chem. 1999, 64, 54-59; d) G. V. M. Sharma, C. G. Reddy, P. R. Krishna, J. Org. Chem. 2003, 68, 4574-4575.
163. Replacing the benzyl ether by the 4-methoxybenzyl ether led to extensive decomposition of the corresponding allyl vinyl ether in the presence of the Lewis acid 1d. OPMB-ethers are know to be cleavable by Lewis acids, see: a) J. Wennerberg, L. Eklund, M. Polla, T. Frejd, J. Chem. Soc. Chem. Commun. 1997, 445; b) J. Wennerberg, C. Olofsson, T. Frejd, J. Org. Chem. 1998, 63, 359 5-3598; c) J. Wennerberg, F. Ek, A. Hansson, T. Frejd, J. Org. Chem. 1999, 64, 54-59; d) G. V. M. Sharma, C. G. Reddy, P. R. Krishna, J. Org. Chem. 2003, 68, 4574-4575.
164. 2Cl, 80°C, 4 d, 84%) of (E,Z)-2d afforded rac-anti-3d exclusively.
165. D. A. Evans, J. S. Johnson, C. S. Burgey, K. R. Campos, Tetrahedron Lett. 1999, 40, 2879-2882.
166. The synthesis and chemistry of α-keto acids has been summarized, see: A. J. L. Cooper, J. Z. Ginos, A. Meister, Chem. Rev. 1983, 83, 321-358.
167. a) Reduction with diisopinocampheylborane, see: P. V. Ramachandran, H. C. Brown, S. Pitre, Org. Lett. 2001, 3, 17-18;
168. b) reduction with sodium borohydride, see: S. Drioli, P. Nitti, G. Pitacco, L. Tossut, E. Valentin, Tetrahedron: Asymmetry 1999, 10, 2713-2728;
169. c) diastereoselective reduction of O-chiral α-keto esters, see: H. Sugimura, K. Yoshida, J. Org. Chem. 1993, 58, 4484-4486;
170. d) diastereoselective reduction of O-chiral α-keto esters, see: A. Solladie-Cavallo, J. Suffert, Tetrahedron Lett. 1985, 26, 429-430;
171. e) diastereoselective reduction of O-chiral α-keto esters, see: T. Akiyama, H. Nishimoto, S. Ozaki, Tetrahedron Lett. 1991, 32, 1335-1338;
172. f) diastereoselective reduction of O-chiral α-keto esters, see: A. Solladie-Cavallo, M. Bencheqroun, Tetrahedron: Asymmetry 1991, 2, 1165-1171.
173. The configuration of the newly generated chiral center at C-2 was assigned based on NOESY studies on the α-hydroxy δ-lactone which is accessible from 8f by TBAF-mediated removal of the TPS-protecting group followed by in situ lactonization. The configuration of 7f was assigned in analogy. Jørgensen has reported an analogous diastereoface-differentiation in favor of the 2,3-anti product as the result of the L-Selectride reduction of an β-chiral α-keto ester, see: K. Juhl, N. Gathergood, K. A. Jørgensen, Angew. Chem. Int. Ed. 2001, 40, 2995-2997; Angew. Chem. 2001, 113, 3083-3085.
174. The configuration of the newly generated chiral center at C-2 was assigned based on NOESY studies on the α-hydroxy δ-lactone which is accessible from 8f by TBAF-mediated removal of the TPS-protecting group followed by in situ lactonization. The configuration of 7f was assigned in analogy. Jørgensen has reported an analogous diastereoface-differentiation in favor of the 2,3-anti product as the result of the L-Selectride reduction of an β-chiral α-keto ester, see: K. Juhl, N. Gathergood, K. A. Jørgensen, Angew. Chem. Int. Ed. 2001, 40, 2995-2997; Angew. Chem. 2001, 113, 3083-3085.
175. For a review, see: A. Mengel, O. Reiser, Chem. Rev. 1999, 99, 1191-1224.