Polymer-Supported IBX-Amide Reagents: Significant Role of Spacer and Additive in Alcohol Oxidation

Abstract

We found that the spacer and additive play a significant role in the oxidation of alkyl alcohols using polymer-supported IBX-amide reagents. The introduction of the spacer between the polymer support and IBX-amide group improved the initial conversion rate (up to 60% conversion). Furthermore, various alcohol compounds, when reacted with IBX-amide resin in the presence of BF₃·OEt₂, were effectively converted into the corresponding aldehydes or ketones within 5-30 minutes in high purities (>94%) at room temperature.

Key words

spacer - additive - IBX-amide resin

References

• 1a McNamara CA. Dixon MJ. Bradley M. Chem. Rev.  2002,  102:  3275 
• 1b Hodge P. Curr. Opin. Chem. Biol.  2003,  7:  362 
• 2a Bhattacharyya S. Comb. Chem. High Throughput Screening  2000,  3:  65 
• 2b Patchornik AH. Polym. Adv. Technol.  2002,  13:  1078 
• 2c Nam N.-H. Sardari S. Parang K. J. Comb. Chem.  2003,  5:  479 
• 3a Hudlicky M. Oxidation in Organic Chemistry   American Chemical Society; Washington, DC: 1990.  p.114-163  
• 3b Lou JD. Lou WX. Synth. Commun.  1997,  27:  3697 
• 3c Mirafzal GA. Lozera M. Tetrahedron Lett.  1998,  39:  7263 
• 4a Fréchet JMJ. Darling P. Farrall MJ. J. Org. Chem.  1981,  46:  1728 
• 4b Mohanazadeh F. Ghamsari S. React. Funct. Polym.  1996,  29:  193 
• 4c Hinzen B. Ley SV. J. Chem. Soc., Perkin Trans. 1  1997,  1907 
• 4d Kessat A. Babadjamian A. Iraqi A. Eur. Polym. J.  2001,  37:  131 
• 4e Tamami B. Karimi Zarchi MA. Eur. Polym. J.  1995,  31:  715 
• 5a Mülbaier M. Giannis A. Angew. Chem. Int. Ed.  2001,  40:  4393 
• 5b Sorg G. Mengel A. Jung G. Rademann J. Angew. Chem. Int. Ed.  2001,  40:  4395 
• 5c Reed NN. Delgado M. Hereford K. Clapham B. Janda KD. Bioorg. Med. Chem. Lett.  2002,  12:  2047 
• 5d Lei Z. Denecker C. Jegasothy S. Sherrington DC. Slater NKH. Sutherland AJ. Tetrahedron Lett.  2003,  44:  1635 
• 6 Chung W.-J. Kim D.-K. Lee Y.-S. Tetrahedron Lett.  2003,  44:  9251 
• 7 Zhdankin VV. Litvinov DN. Koposov AY. Luu T. Ferguson MJ. McDonald R. Tykwinski RR. Chem. Commun.  2004,  106 
• 8a Moriarty RM. Vaid RK. Ravikumar VT. Vaid BK. Hopkins TE. Tetrahedron Lett.  1988,  44:  1603 
• 8b Ochiai M. Miyamoto K. Shiro M. Ozawa T. Yamaguchi K. J. Am. Chem. Soc.  2003,  125:  13006 
• 9 Shukla VG. Salgaonkar PD. Akamanchi KG. J. Org. Chem.  2003,  68:  5422 
• 12a Tohma H. Takizawa S. Watanabe H. Kita Y. Tetrahedron Lett.  1998,  39:  4547 
• 12b Tohma H. Maegawa T. Takizawa S. Kita Y. Adv. Synth. Catal.  2002,  344:  328 
• 13 Soulard M. Block F. Hatterer A. J. Chem. Soc., Dalton. Trans.  1981,  2300 
• 14 Kim D.-K. Chung W.-J. Lee Y.-S. Synlett  2005,  279 
• 16 Kaiser E. Colescott RLC. Bossinger D. Cook PI. Anal. Biochem.  1970,  34:  595 

10

Swelling volume was determined using a column (ID 0.9 cm, length 40 cm) with sintered glass filter. Each resin (500 mg) was swollen in CHCl₃ for 2 h. Thereafter, the solvent was removed by filtration, and the swelling volume of each resin was determined as: resin 1 (4.2 mL/g); resin 2 (3.9 mL/g); resin 3 (3.4 mL/g); resin 4 (3.8 mL/g).

11

Oxidation of 1-decanol (1 equiv) was performed using IBX-amide resin 1 (1.3 equiv) with N-methyl hexanamide (1.3 equiv) in CHCl₃ at r.t. The reaction mixture was analyzed by GC-MS after 3 h and 6 h. The conversion of 1-decanol was compared with that from the oxidation of 1-decanol without N-methyl hexanamide (NMH) under the same condition; 37% (with NMH) and 34% (without NMH) after 3 h, 43% (with NMH) and 44% (without NMH) after 6 h. No reaction between NMH and IBX-amide resin 1 was detected.

15

Three cycles of oxidations with the condition employed in entry 1 (in Table [1] ) and reactivations were investigated. The oxidation capacity was maintained in the range of 0.55-0.59 mmol/g. The conversions of 1-decanol were determined as >97 (run 1), >97 (run 2), and 95% (run 3).