Synthesis of benzyl esters using 2-benzyloxy-1-methylpyridinium triflate

Journal of Organic Chemistry

Volumn 72, Issue 23, 2007, Pages 8962-8964

  Tummatorn, Jumreang ^a   Albiniak, Philip A ^a   Dudley, Gregory B ^a  

^a FLORIDA STATE UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

BENZYL ESTERS; TRIETHYLAMINE;

ALCOHOLS; AMIDES; AMINO ACIDS; CARBOXYLIC ACIDS; DERIVATIVES; ESTERIFICATION; SYNTHESIS (CHEMICAL);

ESTERS;

2 BENZYLOXY 1 METHYLPYRIDINIUM TRIFLATE; ALCOHOL DERIVATIVE; AMIDE; AMINO ACID; BENZYL ALCOHOL ESTER DERIVATIVE; CARBOHYDRATE DERIVATIVE; CARBOXYLIC ACID; ESTER DERIVATIVE; PHENOL DERIVATIVE; PYRIDINIUM DERIVATIVE; TRIETHYLAMINE; UNCLASSIFIED DRUG;

ARTICLE; BENZYLATION; CHEMICAL REACTION; ESTERIFICATION; REACTION ANALYSIS; SYNTHESIS;

CARBOXYLIC ACIDS; COMBINATORIAL CHEMISTRY TECHNIQUES; ESTERS; MESYLATES; MOLECULAR STRUCTURE; PYRIDINIUM COMPOUNDS; STEREOISOMERISM;

EID: 35948952320     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo7018625     Document Type: Article

References (22)

1. (a) Poon, K. W. C.; Albiniak, P. A.; Dudley, G. B. Org. Synth. 2007, 84, 295-305.
2. (b) Poon, K. W. C.; Dudley, G. B. J. Org. Chem. 2006, 71, 3923-3927.
3. (c) Poon, K. W. C.; House, S. E.; Dudley, G. B. Synlett 2005, 3142-3144.
4. PMB transfer reagent: Nwoye, E. O.; Dudley, G. B. Chem. Commun. 2007, 1436-1437.
5. Caubert, V.; Massé, J.; Retailleau, P.; Langlois, N. Tetrahedron Lett. 2007, 48, 381-384.
6. Mukaiyama, T. Angew. Chem., Int. Ed. Engl. 1979, 18, 707-721.
7. (a) Greene, T. W.; Wuts, P. G. M. Protective Groups in Organic Synthesis, 3rd ed.; John Wiley and Sons: New York, 1999.
8. (b) Kocienski, P. J. Protecting Groups, 3rd ed.; Thieme: Stuttgart, 2003.
9. 3N was 93%.
10. 3, also known as benzotrifluoride or BTF, is frequently used industrially as a safer alternative to chlorinated solvents.
11. 2, which provide 4d in only 60% yield: Kokotos, G.; Chiu, A. Synthesis 1997, 168-170.
12. 3, so TCE was employed.
13. In contrast, treatment of 3n with BTCA under reported conditions (see ref 8) resulted in general decomposition with no evidence of 4n.
14. We cannot exclude the possibility of base-promoted racemization events, as we have not measured the enantiomeric purity of any of the compounds reported in this paper.
15. Anhydrous solvents, oven-dried glassware, and inert gas atmospheres were typically employed as part of routine experimental practice, but we took no special precautions in the storage and handling of salt 1 nor of the carboxylic acids, which are likely or known to be hygroscopic.
16. (a) Nicolaou, K. C.; Yue, E. W.; Naniwa, Y.; De Riccardis, F.; Nadin, A.; Leresche, J. E.; La Greca, S.; Yang, Z. Angew. Chem., Int. Ed. Engl. 1994, 33, 2184-2187.
17. (b) Review: Mathias, L. J. Synthesis 1979, 561-576.
18. Or Lewis acid reagents, which likely give rise to protic acid in situ.
19. 2-Benzyloxy-1-methylpyridinium triflate [26189-59-3] is licensed, manufactured, and distributed by Sigma-Aldrich Chemical Co., catalog #679674. See (a) Dudley, G. B. Compounds and methods of arylmethylation (benzylation) as protection for alcohol groups. U. S. Patent Appl. 11/399,-300, 2006.
20. (b) ChemFiles 2007, 7 (3), 3.
21. For Friedel-Crafts benzylation reactions using 1, see: Albiniak, P. A.; Dudley, G. B. Tetrahedron Lett. 2007, DOI: 10.1016/j.tetlet.2007.09.116.
22. For full characterization data, see: Chen, C. T.; Munot, Y. S. J. Org. Chem. 2005, 70, 8625-8627.