3265-74-5Relevant articles and documents
Syntheses and pyrolyses of benzofuran analogues of α-oxo-o- quinodimethane. A study on vinylcarbene-cyclopropene rearrangement
Tseng, Pen-Wen,Yeh, Su-Wen,Chou, Chin-Hsing
, p. 3481 - 3485 (2008/09/21)
(Chemical Equation Presented) Flash vacuum pyrolyses (FVP) of benzoic 3-methyl-2-benzofurancarboxylic anhydride (12) and benzoic 2-methyl-3- benzofurancarboxylic anhydride (13) at 550°C and ca. 10-2 torr both give methylenebenzocyclobutenone (21) as the major product and indenone (22) as the minor one. A mechanism involving generation of α-oxo-o- quinodimethane 11 as the primary pyrolysis product from FVP of 13, followed by elimination of a CO molecule to give carbene 24, which undergoes a vinylcarbene-cyclopropene rearrangement and a ring contraction of the resulting carbene 23, is proposed to account for the observed results. The proposed mechanism is further supported by a deuterium-labeling study on FVP of (2-benzofuryl)methyl-α,α-d2 benzoate (28-d2).
A New Preparation of Benzofurans Utilizing Trimethylsilyldiazomethane
Ito, Yasuko,Aoyama, Toyohiko,Shioiri, Takayuki
, p. 1163 - 1164 (2007/10/03)
o-Triisopropylsiloxyaryl ketones and aldehydes smoothly reacted with the lithium salt of trimethylsilyldiazomethane to give o-triisopropylsiloxyphenylacetylenes which were easily converted to benzofurans by treatment with tetra-n-butylammonium fluoride. 3-Benzofuranmethanols were also obtained when the reaction was conducted in the presence of carbonyl compounds.
