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DOI: 10.1055/s-2007-984915
The Chemistry of α,β-Ditosyloxyketones: Novel Routes for the Synthesis of Desoxybenzoins and α-Aryl-β-ketoaldehyde Dimethylacetals from α,β-Chalcone Ditosylates
Publication History
Publication Date:
20 July 2007 (online)
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Abstract
The reaction of α,b-chalcone ditosylates 3 with potassium hydroxide in suitable conditions leads to 1,2-aryl shift and carbon-carbon bond cleavage, thereby providing a novel route for the synthesis of 1,2-diarylethan-1-ones 4 and 1,2-diaryl-3,3-dimethoxy propan-1-ones 5.
Key words
α,β-ditosyloxyketones - desoxybenzoins - α,β-chalcone ditosylates
- For reviews see:
-
1a
Prakash O.Saini N.Sharma PK. Heterocycles 1994, 38: 409 -
1b
Koser GF. Aldrichimica Acta 2001, 34: 89 -
2a
Prakash O.Rani N.Goyal S. J. Chem. Soc., Perkin Trans 1 1992, 707 -
2b
Mohan J.Verma P.Singh V. Synth. Commun. 1992, 22: 1293 -
2c
Prakash O.Aggarwal R.Saini N.Goyal S.Tomer RK.Singh SP. Indian J. Chem., Sect. B. 1994, 33: 116 -
2d
Mohan J.Singh V.Kumar V.Kataria S. J. Chem. Res., Synop. 1994, 38 -
2e
Singh SP.Batra H.Sharma PK.Prakash O. J. Indian Chem. Soc. 1997, 74: 940 -
2f
Singh SP.Naithani R.Prakash O. J. Indian Chem. Soc. 1998, 75: 770 -
2g
Prakash O.Pundeer R.Chaudhri V. J. Indian Chem. Soc. 2004, 34: 2659 -
2h
Aggarwal R.Pundeer R.Kumar V.Chaudhri V.Singh SP.Prakash O. Synth. Commun. 2004, 34: 2659 -
3a
House HO.Ryerson GD. J. Am. Chem. Soc. 1961, 83: 979 -
3b
Sharma TC.Patel H.Bokadia MM. Indian J. Chem. 1973, 11: 703 -
3c
Weber FG.Radeglia R. J. Prakt. Chem. 1989, 331: 212 -
3d
Holla BS.Shridhara K. Chim. Acta Turc. 1992, 20: 161 -
3e
Saoudi A.Hamelin J.Benhaoua H. J. Chem. Res., Synop. 1996, 491 -
3f
Khurana JM.Seghal A. Synth. Commun. 1996, 26: 3791 -
3g
Elba ME.Darwish AI.Hamada NM. Egypt. J. Chem. 1997, 40: 81 -
3h
Elba ME.Darwish AI.Hamada NM. J. Indian Chem. Soc. 1997, 74: 202 -
3i
Elba ME. Phosphorus, Sulfur Silicon Relat. Elem. 2000, 160: 233 -
3j
Wislicennus W.Ruthing A. Justus Liebigs Ann. Chem. 1911, 379: 299 -
4a
Zhdankin VV.Stang PJ. Chem. Rev. 2002, 102: 2523 -
4b
Moriarty RM. J. Org. Chem. 2005, 70: 2893 - 5
Rebrovic L.Koser GF. J. Org. Chem. 1984, 49: 2462 - 8
Allen CFH.Baker WE. Org. Synth., Coll. Vol. II Wiley; New York: 1943. p.156 - 9
Blay G.Fernandez I.Monje B.Pedro JR. Molecules 2004, 9: 365 - 10
Kim SH.Rieke RD. J. Org. Chem. 2000, 65: 2322 - 11
Veno Y.Okawara M. Synthesis 1975, 268 - 12
Miyashita A.Matsuoka Y.Suzuki Y.Iwamoto K.Hgashino T. Chem. Pharm. Bull. 1997, 45: 1235 - 13
Curtin DY.Crew MC. J. Am. Chem. Soc. 1954, 76: 3719 - 14
Mann W. Ber. Dtsch. Chem. Ges. 1881, 14: 1646 - 15
Hauser CR.Morris GF. J. Org. Chem. 1961, 26: 4740 - 16
Meisenheimer J.Jochelson L. Justus Liebigs Ann. Chem. 1907, 355: 291 - 18
Taylor EC.Conley RA.Johnson DK.McKillop A.Ford ME. J. Org. Chem. 1980, 45: 3433
References and Notes
Experimental Procedure for α,β-Chalcone Ditosylates 3: To a solution of chalcone (1b, 1.11 g, 0.005 mol) in CH2Cl2 (40 mL) was added HTIB (3.92 g, 0.01 mol). The resulting mixture was allowed to stir at 40-42 °C. HTIB was highly insoluble in CH2Cl2, but gradually disappeared as the reaction proceeded. The stirring was allowed to continue for about 16-18 h. The solvent was evaporated in vacuo. The gummy mass so obtained was triturated with PE (60-80 °C) to remove iodobenzene. The colorless solid obtained was thoroughly washed with H2O to remove p-toluenesulfonic acid formed as byproduct. The solid was recrystallized from MeCN to give the pure chalcone ditosylate 3b; yield: 1.66 g (59%); mp 114-115 °C. IR (KBr): 1675 (CO stretch) cm-1. 1H NMR (300 MHz, CDCl3): δ = 2.21 (s, 3 H, Me), 2.43 (s, 6 H, Me), 5.00 (d, J = 8.1 Hz, 1 H, CH), 6.97 (d, J = 8.1 Hz, 1 H, CH), 6.80-6.87 (m, 2 H, ArH), 7.10-7.21 (m, 4 H, ArH), 7.32-7.35 (m, 3 H, ArH), 7.38-7.48 (m, 4 H, ArH), 7.71-7.79 (m, 4 H, ArH). Anal. Calcd for C30H28O7S2: C, 63.8; H, 4.9. Found: C, 62.7; H, 4.2.
Other derivatives 3a, 3c-3j were prepared in a similar manner.
Experimental Procedure for Desoxybenzoins 4: To a solution of α,β-chalcone ditosylate 3a (0.550 g, 0.01 mol) in EtOH (20 mL) was added KOH (0.112 g, 0.02 mol). The mixture was heated under reflux for 2-3 h. The progress of the reaction was monitored by TLC. When all of the starting material had been consumed, the reaction mixture was poured over crushed ice, extracted with CH2Cl2 and the crude product 4a was purified by column chromatography using EtOAc-PE as eluent; yield: 0.114 g (58%); mp 52-54 °C (Lit. mp 55-56 °C). IR (KBr): 1685 (CO stretch) cm-1. 1H NMR (300 MHz, CDCl3): δ = 4.18 (s, 2 H, CH2), 7.12-7.13 (m, 2 H, ArH), 7.51-7.70 (m, 6 H, ArH), 7.99-8.21 (m, 2 H, ArH).
Other derivatives 4b-j were prepared in a similar manner.
Experimental Procedure for α-Aryl-β-ketoaldehyde Dimethylacetals 5: To a solution of α,β-chalcone ditosylate 3a (0.550 g, 0.01 mol) in EtOH (20 mL) was added KOH in catalytic amount. The mixture was stirred at r.t. for about 2 h and was heated under reflux for 2-3 h. The reaction mixture was poured over crushed ice. The crude product 5a was purified by recrystallization using MeOH as a solvent; yield: 0.138 g (51%); mp 93-94 °C (Lit.18 mp 94.5-96.5 °C). IR (KBr): 1682 (CO stretch) cm-1. 1H NMR (300 MHz, CDCl3): δ = 3.28 (s, 3 H, OMe), 3.49 (s, 3 H, OMe), 4.92 (d, J = 9.0 Hz, 1 H, CH), 5.16 (d, J = 9.0 Hz, 1 H, CH), 7.04-7.05 (m, 2 H, ArH), 7.39-7.68 (m, 6 H, ArH), 7.97-8.08 (m, 2 H, ArH).
Other derivatives 5b-5j were prepared in a similar manner.