1236076-71-3Relevant articles and documents
Convenient access to various 1-cyclopropylcyclopropane derivatives
De Meijere, Armin,Khlebnikov, Alexander F.,Suennemann, Hans Wolf,Frank, Daniel,Rauch, Karsten,Yufit, Dmitrii S.
, p. 3295 - 3301 (2010)
1-Bromo-1-cyclopropylcyclopropane (1), which is easily accessible in two steps from methyl cyclopropanecarboxylate, does not form a stable Grignard reagent: upon reaction with elemental magnesium, yet it readily undergoes bromine/ lithium exchange without rearrangement upon treatment with tert-butyllithium in diethyl ether/pentane at -78 °C, and the resulting 1-lithio-1-cyclopropylcyclopropane can be trapped with various electrophiles to give the correspondingly 1-substituted bicyclopropyl derivatives 10 in yields ranging from 38 to over 90 % (13 examples). The (1-cyclopropylcyclopropyl) boronate 10m, which is also obtained from the 1-lithio derivative, has been subjected to Suzuki cross couplings with a number of aryl halides to furnish 1-aryl-1,1′bicyclopropyl compounds 11 (4 examples, 14-50% yield), predominantly without rearrangement. Further transformations of 1-cyclopropylcyclopropanecarbaldehyde (10e) have provided 2-(1- cyclopropylcyclopropyl)glycme (16), ethyl 3-(1-cyclopropylcyclopropyl)acrylate (17), and its cycloadducts with the nitrone 18 and cyclopentadiene 19, albeit the latter only in poor yield.
