Synlett 2002(3): 0407-0410
DOI: 10.1055/s-2002-20452
LETTER
© Georg Thieme Verlag Stuttgart · New York

A New and Mild Heterogeneous Catalytic Decomposition of α-Diazo Carbonyl Compounds Using Montmorillonite or Zeolite

Sengodagounder Muthusamy*, Srinivasarao Arulananda Babu, Chidambaram Gunanathan, Raksh Vir Jasra
Silicates and Catalysis Discipline, Central Salt and Marine Chemicals Research Institute, Bhavnagar 364 002, India
Fax: +91(278)567562; e-Mail: salt@csir.res.in;
Further Information

Publication History

Received 11 December 2001
Publication Date:
05 February 2007 (online)

Abstract

A very mild method of decomposition of various α-diazo carbonyl compounds 1 in the presence of environmentally attractive solid acids such as montmorillonite K-10 or zeolite H-Y in a heterogeneous manner to furnish α-hydroxy/alkoxy ketones in very good yield is reported. Interestingly, novel bicycloalkane-1,3-diones and 3-furanones were obtained as unusual products in the case of aliphatic/alicyclic α-diazo carbonyl compounds.

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Typical Experimental Procedure: The clay/zeolite catalysts used in this work were activated at 200 °C for 3 h. To a solution containing α-diazo ketone 1a (100 mg) in commercial grade dichloromethane was added zeolite H-Y (175 mg) or montmorillonite clay K-10 (175 mg) and the mixture stirred at r.t. or ultrasonicated. Slow nitrogen evolution took place and the reaction mixture was followed by TLC until disappearance of starting material. The reaction mixture was then filtered, concentrated under reduced pressure and purified by silica gel column chromatography to afford product 2a. All novel compounds gave satisfactory spectral data consistent with their structures. Selected spectral data of 5-Hydroxy-4,4,5-trimethyldihydrofuran-3-one (8): colourless solid, mp 63-65 ºC; IR (KBr): 3372, 2998, 2978, 2913, 2934, 1744, 1704, 1471, 1453, 1396, 1121, 1039, 932, 851 cm-1; 1H NMR (200 MHz, CDCl3): δ = 4.14, (d, 1 H, J = 16.6 Hz, OCH2), 4.06 (d, 1 H, J = 16.6 Hz, OCH2), 2.72 (s, 1 H, OH), 1.50 (s, 3 H, CH3), 1.09 (s, 3 H, CH3), 1.05 (s, 3 H, CH3); 13C NMR (50.3 MHz, CDCl3): δ = 16.5 (CH3), 22.0 (CH3), 22.3 (CH3), 51.1 (quat-C), 67.9 (OCH2), 107.4 (quat-C), 218.6 (C=O); MS: m/z = 144 [M+]; Anal. Calcd for C7H12O3: C, 58.31; H, 8.39. Found: C, 58.40; H, 8.44. 2-Methoxy-1-(4-methoxyphenyl)ethanone (11d): colourless thick liquid; IR(neat): 3059, 2934, 2842, 1776, 1691, 1602, 1576, 1512, 1462, 1422, 1312, 1259, 1175, 1128, 1026 cm-1; 1H NMR (200 MHz, CDCl3): δ = 7.93 (d, 2 H, J = 8.6 Hz, Arom-H), 6.93 (d, 2 H, J = 8.6 Hz, Arom-H), 4.65 (s, 2 H, OCH2), 3.87 (s, 3 H, OCH3), 3.50 (s, 3 H, OCH3); 13C NMR (50.3 MHz, CDCl3): δ = 55.9 (OCH3), 59.8 (OCH3), 75.5 (OCH2), 114.0 (=CH), 130.6 (=CH), 133.2 (quat-C), 164.2 (quat-C), 195.1 (C=O); MS: m/z = 180 [M+]; Anal. Calcd for C10H12O3: C, 66.65; H, 6.71. Found: C, 66.72; H, 6.65.