Synlett 2011(19): 2862-2866  
DOI: 10.1055/s-0031-1289857
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

Iron-Catalyzed Reductive Dehydroxylation of Benzylic Alcohols Using Polymethylhydrosiloxane (PMHS)

Li Yan Chan, Jazreel Seh Kai Lim, Sunggak Kim*
Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
Fax: +65(6791)1961; e-Mail: sgkim@ntu.edu.sg;
Further Information

Publication History

Received 12 August 2011
Publication Date:
09 November 2011 (online)

Abstract

The combination of FeCl3 and PMHS is an efficient reducing system for the selective dehydroxylation of secondary benzylic alcohols, even in the presence of carbonyls, under very mild conditions.

    References and Notes

  • 1a Walker ERH. Chem. Soc. Rev.  1976,  5:  23 
  • 1b Brown HC. Krishnamurthy S. Tetrahedron  1979,  35:  567 
  • 1c Kim S. Pure Appl. Chem.  1987,  59:  567 
  • 1d Yoon NM. Pure Appl. Chem.  1996,  68:  843 
  • 1e Yamamura S. Nishiyama S. In Comprehensive Organic Synthesis   Vol. 8:  Trost BM. Fleming I. Pergamon Press; New York: 1991.  p.307-325  
  • 2 Sauer RO. Scheiber WJ. Brewer SD. J. Am. Chem. Soc.  1946,  68:  962 
  • 3a Klyaschitskaya AL. Krasovskii GN. Fridlyand SA. Gig. Sanit.  1970,  35:  28 
  • 3b Ikarashi Y. Tsuchiya T. Nakamura A. J. Toxicol., Cutan. Ocul. Toxicol.  1993,  12:  15 
  • 4a Lawrence NJ. Drew MD. Bushell SM. J. Chem. Soc., Perkin Trans. 1  1999,  3381 
  • 4b Carpentier J.-F. Bette V. Curr. Org. Chem.  2002,  6:  913 
  • 5 Lipowitz J. Bowman SA. J. Org. Chem.  1973,  38:  162 
  • 6a Halterman RL. Ramsey TM. Chen ZL. J. Org. Chem.  1994,  59:  2642 
  • 6b Carter MB. Schiøtt B. Gutiérrez A. Buchwald SL. J. Am. Chem. Soc.  1994,  116:  11667 
  • 7a Keinan E. Greenspoon N. J. Org. Chem.  1983,  48:  3545 
  • 7b Blum J. Pri-Bar I. Alper H. J. Mol. Catal.  1986,  37:  359 
  • 8a Chandrasekhar S. Reddy YR. Ramarao C. Synth. Commun.  1997,  27:  2251 
  • 8b Mimoun H. J. Org. Chem.  1999,  64:  2582 
  • 8c Mimoun H. De Saint Laumer J.-Y. Giannini L. Scopelliti R. Floriani C. J. Am. Chem. Soc.  1999,  121:  6158 
  • 8d Riant O. Mostefaï N. Courmacel J. Synthesis  2004,  2943 
  • 9a Beller M. Shaikh NS. Junge K. Org. Lett.   2007,  9:  5429 
  • 9b Beller M. Enthaler S. Junge K. Angew. Chem. Int. Ed.  2008,  47:  3317 
  • 9c Furuta A. Nishiyama H. Chem. Commun.  2007,  760 
  • 9d Shaikh NS. Enthaler S. Junge K. Beller M. Angew. Chem. Int. Ed.  2008,  47:  2497 
  • 9e Langlotz BK. Wadepohl H. Gade LH. Angew. Chem. Int. Ed.  2008,  47:  4670 
  • 10a Chandrasekhar S. Reddy CR. Babu BN. J. Org. Chem.  2002,  67:  9080 
  • 10b Geovorgyan V. Liu J.-X. Rubin M. Benson S. Yamamoto Y. Tetrahedron Lett.  1999,  40:  8919 
  • 10c Geovorgyan V. Rubin M. Benson S. Liu J.-X. Yamamoto Y. J. Org. Chem.  2000,  65:  6179 
  • 11 Vedejs E. Org. React.  1975,  22:  401 
  • For reviews, see:
  • 12a Todd D. Org. React.  1948,  4:  378 
  • 12b Hutchins RO. Hutchins MK. In Comprehensive Organic Synthesis   Vol. 8:  Trost BM. Fleming I. Pergamon Press; New York: 1991.  p.328-362  
  • For reviews, see:
  • 13a Bolm C. Legros J. Paih JL. Zani L. Chem. Rev.  2004,  104:  6217 
  • 13b Iron Catalysis in Organic Chemistry: Reactions and Applications   Plietker B. Wiley-VCH; Weinheim: 2008. 
  • 13c Sherry BD. Fürstner A. Acc. Chem. Res.  2008,  41:  1500 
  • 13d Correa A. Garcia Mancheno O. Bolm C. Chem. Soc. Rev.  2008,  37:  1108 
  • 13e Czaplik WM. Mayer M. Cvengros J. Von Wangelin AJ. ChemSusChem  2009,  2:  396 
  • 14 Campagne J.-M. Zotto CD. Virieux D. Synlett  2009,  276 
  • 15a Eisch JJ. Liu Z.-R. Boleslawski MP. J. Org. Chem.  1992,  57:  2143 
  • 15b Miyai T. Ueba M. Baba A. Synlett  1999,  182 
  • 15c Yasuda M. Onishi Y. Ueda M. Miyai T. Baba A. J. Org. Chem.  2001,  66:  7741 
  • 15d Yao M.-J. Pippin AB. Kabalka GW. Tetrahedron Lett.  2010,  51:  853 
  • 16a Kabalka GW. Yao M.-L. Borella S. Wu Z.-Z. Org. Lett.  2005,  7:  2865 
  • 16b Kabalka GW. Yao M.-L. Borella S. Org. Lett.  2006,  8:  879 
  • 16c Kabalka GW. Yao M.-L. Borella S. Wu Z.-Z. Chem. Commun.  2005,  2492 
  • 17 Chan LY. Kim S. Chung WT. Long C. Kim S. Synlett  2011,  415 
  • 18a Kim S. Chung KN. Yang S. J. Org. Chem.  1987,  52:  3917 
  • 18b Sharma GVM. Kumar KR. Sreenivas P. Krishna PR. Chorghade MS. Tetrahedron: Asymmetry  2002,  13:  687 
  • 18c Kim SH. Shin C. Pai AN. Koh HK. Chang MH. Chung BY. Cho YS. Synthesis  2004,  1581 
  • 18d Terrassson V. Marque S. Georgy M. Campagne J.-M. Prim D. Adv. Synth. Catal.  2006,  348:  2063 
  • 19 Zhou S. Junge K. Addis D. Das S. Beller M. Angew. Chem. Int. Ed.  2009,  48:  9507 
20

General procedure for the reductive dehydroxylation of benzylic alcohols 4: Anhydrous FeCl3 (2.4 mg, 0.015 mmol, 5 mol% equiv) was carefully weighed and stirred in 1,2-dichloroethane (2 mL) for 5 min. PMHS (0.05 mL, 0.9 mmol, 3.0 equiv) was then added to the prepared catalyst solution, followed by benzylic alcohol 4 (0.3 mmol, 1.0 equiv) and stirred at either r.t. or heated to the respective temperature. The residual crude product was concentrated in vacuo and purified by flash chromatography to afford the desired product 5. ¹H NMR and ¹³C NMR data of previously unknown compounds: 4-heptyl-1,2-dimethoxybenzene (5d). ¹H NMR (400 MHz, CDCl3): δ = 7.26-6.70 (m, 3 H), 3.87 (s, 3 H), 3.85 (s, 3 H), 2.54 (t, J = 7.8 Hz, 2 H), 1.60-0.86 (m, 13 H); ¹³C NMR (100 MHz, CDCl3): δ = 148.7, 147.0, 135.6, 120.1, 111.8, 111.2, 55.9, 55.8 35.6, 31.8, 31.7, 29.3, 29.2, 22.7, 14.1; HRMS (ESI): m/z [M + 1] calcd for C15H25O2: 237.1855; found: 237.1850. 1-Bromo-4-heptyl-benzene (5k):¹¹ ¹H NMR (400 MHz, CDCl3): δ = 7.37 (d, J = 8.3 Hz, 2 H), 7.03 (d, J = 8.3 Hz, 2 H), 2.54 (t, J = 7.8 Hz, 2 H), 1.63-1.53 (m, 2 H), 1.36-1.19 (m, 8 H), 0.88 (t, J = 6.8 Hz, 3 H); ¹³C NMR (100 MHz, CDCl3): δ = 141.8, 131.2, 130.1, 119.2, 35.3, 31.8, 31.3, 29.1, 29.1, 22.6, 14.1; HRMS (ESI): m/z [M + 1] calcd for C13H20Br: 255.0748; found: 255.0757.