Deprotonation of benzylic ethers using a hindered phosphazene base. A synthesis of benzofurans from Ortho-substituted benzaldehydes

Organic Letters

Volumn 2, Issue 16, 2000, Pages 2409-2410

  Kraus, George A ^a   Zhang, Ning ^a   Verkade, John G ^a   Nagarajan, Muthukaman ^a   Kisanga, Philip B ^a  

^a IOWA STATE UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

BENZALDEHYDE DERIVATIVE; BENZOFURAN DERIVATIVE; DYES, REAGENTS, INDICATORS, MARKERS AND BUFFERS; ORGANOPHOSPHORUS COMPOUND;

ARTICLE; CHEMICAL STRUCTURE; CHEMISTRY; CONFORMATION; SYNTHESIS;

BENZALDEHYDES; BENZOFURANS; INDICATORS AND REAGENTS; MOLECULAR CONFORMATION; MOLECULAR STRUCTURE; ORGANOPHOSPHORUS COMPOUNDS;

EID: 0034632434     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol0000758     Document Type: Article

References (20)

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19. 4-t-Bu (0.46 mmol as a 1 M solution in hexane available from Fluka) at room temperature. The reaction was then carried out at the temperature given in Table 1. When the reaction was complete, as indicated by TLC, the reaction mixture was loaded directly onto a 40-140 mesh silica gel column and eluted with 2% ethyl acetate in hexanes to give pure 2-arylated benzofurans in good to moderate yields. Entry 1 of Table 1: Oishi, K.; Kurosawa, K. Bull. Chem. Soc. Jpn. 1980, 53, 179. Entry 7 of Table 1: mp 177-179 °C (177-178 °C, Colas, C.; Goeldner, M. Eur. J. Org. Chem. 1999, 1357).
20. 4-t-Bu (0.46 mmol as a 1 M solution in hexane available from Fluka) at room temperature. The reaction was then carried out at the temperature given in Table 1. When the reaction was complete, as indicated by TLC, the reaction mixture was loaded directly onto a 40-140 mesh silica gel column and eluted with 2% ethyl acetate in hexanes to give pure 2-arylated benzofurans in good to moderate yields. Entry 1 of Table 1: Oishi, K.; Kurosawa, K. Bull. Chem. Soc. Jpn. 1980, 53, 179. Entry 7 of Table 1: mp 177-179 °C (177-178 °C, Colas, C.; Goeldner, M. Eur. J. Org. Chem. 1999, 1357).