A green and selective reduction of aldehydes

Tetrahedron Letters

Volumn 41, Issue 19, 2000, Pages 3523-3526

  Bryson, T A ^a   Jennings, J M ^a   Gibson, J M ^b  

^a UNIVERSITY OF SOUTH CAROLINA   (United States)

^b WINGATE UNIVERSITY   (United States)

Author keywords

Selective aldehyde reduction; Subcritical water

Indexed keywords

ALCOHOL; ALDEHYDE DERIVATIVE; CYCLOPENTANONE DERIVATIVE; FORMIC ACID DERIVATIVE; KETONE DERIVATIVE; WATER;

ARTICLE; CATALYST; CHEMICAL ANALYSIS; CHEMICAL MODIFICATION; HIGH TEMPERATURE; PRESSURE; REDUCTION;

EID: 0034611932     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(00)00435-4     Document Type: Article

References (18)

1. For Green Chemistry, see: http://www.epa.gov/opptintr/greenchemistry/whatis.htm.
2. (a) Hutchins, R. O. J. Amer. Chem. Soc. 1973, 95, 6131.
3. (b) Maki, Y.; Kikuchi, K.; Sugiyama, H.; Seto, S. Tetrahedron Lett. 1977, 263.
4. Trost, B. M. The atom economy - A search for synthetic efficiency. Science 1991, 254, 1471.
5. 2O or NaOH.
6. Equipment: Two types of reactors have been employed: A Parr pressure reactor heated in a sand bath or oven and a capped 316 stainless steel tube heated in a muffle oven. The latter can be equipped with a thermocouple and fiber optic probe.
7. Johnstone, R. A. W.; Wilby, A. H.; Entwistle, I. D. Chem. Rev. 1985, 85, 129.
8. Reductions in Organic Chemistry, 2nd Edn.; Hudlicky, M.; ACS Monograph 188, ACS: Washington, DC, 1996; p. 15, and references cited therein.
9. For reduction of carbonyls with alcohols, see: (a) Bagnell, L.; Strauss, C. Chem. Commun. 1999, 287.
10. (b) Malwitz, D.; Metzger, J. O. Angew. Chem., Int. Ed. Engl. 1986, 25, 762.
11. (c) Malwitz, D.; Metzger, J. O. Chem. Ber. 1986, 119, 3558.
12. Calculation of Pressure: Introduction to Thermodynamics and Heat Transfer; Çenge, Y. A.; The McGraw-Hill Companies: New York, 1997; pp. 849-855.
13. Connelly, J. F. J. Chem. Eng. Data 1966, 11, 13.
14. GC analysis of products indicates yields are much better than reported above.
15. Based on data from GC-mass spectra of the products, it appears aldol/dehydration (2,4-diphenylbut-2-enal) and subsequent reduction (2,4-diphenylbut-2-en-1-ol) are the major reactions with this highly enolizable aldehyde.
16. Product analysis shows 60% of 11 plus a mixture of enol ethers (18%) presumably formed from dehydration of the hemiacetal on heating (GC or distillation). These same products formed on hydrolysis of the ketal of 11. Amounts of 12 were based on GC comparison to an authentic, epimeric sample.
17. 1H NMR, mass spectroscopy and chromatographic comparison to authentic compounds. Some work-up procedures required pH adjustment and chromatography.
18. Preliminary results indicate that ethyl formate affords a similar selectivity for aldehyde reduction. The primary difference observed, so far, between sodium formate (basic) and ethyl formate is that the latter tends to promote dehydration of certain alcohol reduction products.