A synthesis of esters, amides, and sulfones bearing a 1-cyclopentenyl group at the α-position from cyclobutanones with one-carbon ring-expansion
作者:Tsuyoshi Satoh、Yu Awata、Shingo Ogata、Shimpei Sugiyama、Masami Tanaka、Motoo Tori
DOI:10.1016/j.tetlet.2009.02.053
日期:2009.4
derived from cyclobutanones and chloromethyl p-tolyl sulfoxide, with lithium enolate of carboxylic acid tert-butyl esters, lithium enolate of carboxylic acid N,N-dimethylamides, or lithium α-carbanion of alkyl phenyl sulfones gave adducts in high yields. The adducts were treated with isopropylmagnesium chloride or ethylmagnesium chloride in dry toluene to give esters, amides, and sulfones bearing a 1-cyclopentenyl
Synthesis, including asymmetric synthesis, of 1-substituted cyclopentenes from cyclobutanones with one-carbon ring-expansion by 1,2-carbon-carbon insertion of magnesium carbenoids
Treatment of 1-chlorovinyl p-tolyl sulfoxides, which were derivedfrom cyclobutanones and chloromethyl p-tolyl sulfoxide, with lithium enolate of tert-butyl carboxylates, amides, lithium α-sulfonyl carbanions, and lithium α-carbanion of acetonitrile gave adducts in high to quantitative yields. The adducts were treated with Grignard regents, such as i-PrMgCl and EtMgCl in toluene to afford 1-substituted