34721-76-1Relevant academic research and scientific papers
Catalytic enantioselective hydroboration of cyclopropenes
Rubina, Marina,Rubin, Michael,Gevorgyan, Vladimir
, p. 7198 - 7199 (2003)
2,2-Disubstituted cyclopropyl boronates have been synthesized with high degrees of diastereo- and enantioselectivity via the rhodium-catalyzed asymmetric hydroboration of 3,3-disubstituted cyclopropenes. A strong directing effect of ester and alkoxymethyl substituents has been demonstrated. The directing effect was found to be necessary in achieving high degrees of enantiomeric induction. Selected cyclopropylboronic derivatives were successfully employed in the Suzuki cross-coupling reaction to produce the corresponding optically active aryl- and vinylcyclopropanes in good yields. Copyright
Azide Radical Initiated Ring Opening of Cyclopropenes Leading to Alkenyl Nitriles and Polycyclic Aromatic Compounds
Muriel, Bastian,Waser, Jerome
supporting information, p. 4075 - 4079 (2021/01/18)
We report herein a radical-mediated amination of cyclopropenes. The transformation proceeds through a cleavage of the three-membered ring after the addition of an azide radical on the strained double bond and leads to tetrasubstituted alkenyl nitrile derivatives upon loss of N2. With 1,2-diaryl substituted cyclopropenes, this methodology could be extended to a one-pot synthesis of highly functionalized polycyclic aromatic compounds (PACs). This transformation allows the synthesis of nitrile-substituted alkenes and aromatic compounds from rapidly accessed cyclopropenes using only commercially available reagents.
From cyclopropenes to tetrasubstituted furans: Tandem isomerization/ alkenylation sequence with Cu/Pd relay catalysis
Song, Chuanling,Ju, Lin,Wang, Mingchao,Liu, Pengcheng,Zhang, Yuanzhe,Wang, Jianwu,Xu, Zhenghu
supporting information, p. 3584 - 3589 (2013/04/10)
Pon de relay: A convenient and efficient synthesis of alkene-functionalized furans from cyclopropenes, which proceeds through an isomerization/olefination cascade sequence under copper-palladium relay catalysis, has been developed (see scheme). Copyright
An efficient and general method for resolving cyclopropene carboxylic acids
Liao, Lian-An,Zhang, Fan,Yan, Ni,Golen, James A.,Fox, Joseph M.
, p. 1803 - 1816 (2007/10/03)
A general method is described for the resolution of cycloprop-2-ene carboxylic acids via diastereomeric N-acyloxazolidines prepared from enantiomerically pure oxazolidinones. Although a number of oxazolidinones were shown to resolve cyclopropene carboxylic acids, the oxazolidinones of S-phenylalaninol, S-phenylglycine and (1S,2R)-cis-1-amino-2-indanol are optimal in terms of resolving power and cost effectiveness. Separations were performed using simple flash chromatography, and because there is typically a large difference in Rf values it is possible to separate gram quantities of pure diastereomers in a single chromatogram. The cycloprop-2-ene carboxylic acids that can be resolved include those that are substituted at the 1-position by H, Ph, α-naphthyl, CO2Me, CH2OMOM, and trans-styryl; alkene substituents include Me, n-alkyl, Ph and tethered alkynes. Remarkably, 2-methyl-3-propylcycloprop-2-ene carboxylic acid can also be resolved with ease. The relative configurations of four diastereomerically pure oxazolidines were determined by X-ray crystallography. Reduction of the N-acyloxazolidinones with LiBH4 give enantiomerically pure derivatives of 3-hydroxymethylcyclopropene that react with either MeMgCl or vinylMgCl and catalytic CuI to give enantiomerically pure products of syn-addition.
