1041479-83-7Relevant articles and documents
Efficient synthesis of cyclopropanecarboxylic acid esters starting from the conjugate addition of lithium ester enolates to 1-chlorovinyl p -Tolyl sulfoxides
Kimura, Tsutomu,Hattori, Yoshiaki,Momochi, Hitoshi,Nakaya, Nobuhito,Satoh, Tsuyoshi
, p. 483 - 486 (2013)
An efficient synthesis of tert-butyl cyclopropanecarboxylates was achieved in three steps using 1-chlorovinyl p-tolyl sulfoxides as key materials. The conjugate addition of lithium ester enolates to the sulfoxides gave tert-butyl 4-chloro-4-(p-tolylsulfinyl)butanoates in high yield. The p-tolylsulfinyl group in the resultant adducts was then removed by the sulfoxide-magnesium exchange reaction with i-PrMgCl at -60 °C. Cyclization of the desulfinylated products, tert-butyl 4-chlorobutanoates, took place in the presence of NaHMDS in a THF-DMPU mixture to afford tert-butyl cyclopropanecarboxylates in good yield. The asymmetric synthesis of both enantiomers of tert-butyl cyclopropanecarboxylate was successfully achieved using optically active (E)- and (Z)-sulfoxides with high enantiomeric excesses. Georg Thieme Verlag Stuttgart · New York.
A synthesis of bicyclo[n.1.0]alkanes having tert-butyl carboxylate or acetamide moiety via the intramolecular 1,3-CH insertion of magnesium carbenoids
Ogata, Shingo,Saitoh, Hideki,Wakasugi, Daisuke,Satoh, Tsuyoshi
, p. 5711 - 5720 (2008/09/21)
Treatment of 1-chlorovinyl p-tolyl sulfoxides, derived from various cyclic ketones and chloromethyl p-tolyl sulfoxide, with lithium enolate of carboxylic acid tert-butyl esters or N,N-dimethylacetamide gave adducts in high yields. The adducts were treated with ether solution of isopropylmagnesium chloride in dry toluene to give bicyclo[n.1.0]alkane derivatives having tert-butyl carboxylate or acetamide moiety on the bridgehead carbon in high to quantitative yields via magnesium carbenoid 1,3-CH insertion reaction. The 1,3-CH insertion reaction proved to be regioselective and stereospecific. The reaction mechanism and origin of the selectivity and specificity are discussed.
