A bench-stable organic salt for the benzylation of alcohols

Synlett

Volumn , Issue 20, 2005, Pages 3142-3144

  Poon, Kevin W C ^a   House, Sarah E ^a   Dudley, Gregory B ^a  

^a FLORIDA STATE UNIVERSITY   (United States)

Author keywords

Alcohols; Benzyl ethers; Protecting groups; Synthesis

Indexed keywords

ALCOHOL; BENZYL DERIVATIVE; ETHER DERIVATIVE; ORGANIC COMPOUND;

ARTICLE; BENZYLATION; CARBON NUCLEAR MAGNETIC RESONANCE; CHEMICAL REACTION; CHEMICAL STRUCTURE; PROTON NUCLEAR MAGNETIC RESONANCE; SYNTHESIS;

EID: 29744438054     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-2005-921898     Document Type: Article

References (13)

1. (a) Greene, T. W.; Wuts, P. G. M. Protective Groups in Organic Synthesis, 3rd ed.; John Wiley and Sons: New York, 1999.
2. (b) Kocienski, P. J. Protecting Groups, 3rd ed.; Thieme: Stuttgart, 2003.
3. TfOH is generally required, whereas milder acids will promote the formation of p-methoxybenzyl ethers; see ref. 1.
4. Scattered literature reports provided the foundation for this work. In particular, alkoxypyridinium bromides decompose to pyridones and alkyl bromides via nucleophilic attack of the bromide ion (ref. 4), whereas alkoxypyridinium sulfonates are isolable (ref. 5). Note that Mukaiyama's reagent (ref. 6) has been employed to convert alcohols into thioesters and azides.
5. Joshi, R. A.; Ravindranathan, T. Indian J. Chem., Sect. B: Org. Chem. Incl. Med. Chem. 1984, 23, 260.
6. (a) Beattie, D. E.; Crossley, R.; Dickinson, K. H.; Dover, G. M. Eur. J. Med. Chem. 1983, 18, 211.
7. (b) See also: Kornblum, N.; Coffey, G. P. J. Org. Chem. 1966, 31, 3449.
8. For leading references, see: (a) Hojo, K.; Yoshino, H.; Mukaiyama, T. Chem. Lett. 1977, 437.
9. (b) Hojo, K.; Kobayashi, S.; Soai, K.; Ikeda, S.; Mukaiyama, T. Chem. Lett. 1977, 635.
10. (a) Serio, A. J.; Duggan, E.; Grabowski, J. J.; Russ, W. K. Synthesis 1980, 573.
11. (b) Cherng, Y.-J. Tetrahedron 2002, 58, 4931.
12. (c) We prepared 1 by the following procedure, which is a modification of that reported in ref. 7a: A toluene solution of benzyl alcohol (0.5 M, 1.0 equiv), 2-chloropyridine (1.2 equiv), KOH (3.2 equiv, powdered with a mortar and pestle), and 18-crown-6 (0.05 equiv) was heated at reflux for 1 h with azeotropic removal of water. Routine aqueous workup and purification on silica gel afforded 1 in 96% yield.
13. Widmer, U. Synthesis 1987, 568.