96114-04-4Relevant academic research and scientific papers
Simple large-scale preparation of 1,2,3-tris-acceptor substituted cyclopropanes
Kozhushkov, Sergei I.,Leonov, Andrei,De Meijere, Armin
, p. 956 - 958 (2007/10/03)
Triethyl (1α,2α,3β)cyclopropane-1,2,3-tricarboxylate (3aa), as well as diethyl (4ab) and dimethyl (1α,2β,3α)-1-acetylcyclopropane-2,3-dicarboxylate (4bb) have been prepared on a scale of up to 60 g by Michael initiated ring-closure (MIRC) cyclopropanation of dialkyl fumarates 1a,b with ethyl chloroacetate (2a) and chloroacetone (2b) in 62%, 51% and 56% yield, respectively. For the success of the new procedure it is essential to slowly add (within 5-7 h) the mixture of compounds 1 and 2 to a vigorously stirred suspension of K2CO3 in DMF in the presence of benzyltriethylammonium chloride.
