108198-94-3Relevant articles and documents
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Rahman,A.,Clapp,L.B.
, p. 122 - 125 (1976)
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Pd Catalysis in Cyanide-Free Synthesis of Nitriles from Haloarenes via Isoxazolines
Maestri, Giovanni,Ca?eque, Tatiana,Della Ca, Nicola,Derat, Etienne,Catellani, Marta,Chiusoli, Gian Paolo,Malacria, Max
supporting information, p. 6108 - 6111 (2016/12/09)
A method to obtain aryl nitriles from the corresponding halides by Pd catalysis, in the absence of any cyanide source, is reported. The reaction of an aryl halide, ethyl nitroacetate, and an olefin readily delivers an aromatic nitrile. A variety of aryl iodides/bromides have been converted into the corresponding cyanoarenes in fair to excellent yields. The reaction likely involves the following steps: (a) Pd-catalyzed α-arylation of ethyl nitroacetate; (b) nitrile oxide formation; (c) [3 + 2]-cycloaddition with an olefin to provide an isoxazoline; (d) isoxazoline cleavage to benzonitrile formation.
Diastereoselective 1,3-dipolar cycloadditions of both electronically modified phenyl-nitrile oxides and stilbenes
Romanski, Jan,Nowak, Piotr,Maksymiuk, Anna,Chapuis, Christian,Jurczak, Janusz
, p. 23105 - 23118 (2013/11/19)
Menthyl carboxyloyl nitrile oxide addition is less selective for (E)-stilbene (12% d.e.) than for its corresponding (1R)-8-phenyl-menthyl (38% d.e.) or (2R)-bornane[10,2]sultam (48% d.e.) analogues. This lower selectivity is also observed when the chiral auxiliary is placed on the dipolarophile, as demonstrated by the [3 + 2] cycloadditions of p-NO2-phenyl nitrile oxide to acryloyl derivatives of (1R)-menthol (4% d.e.) and (2R)-bornane[10,2] sultam (60% d.e.). We managed to increase these diastereoselectivities by taking advantage of the Tolbert and Ali co-operative influence of two prosthetic groups, as seen in phenyl nitrile oxide addition to the bis-fumaroyl derivatives of (1R)-menthol (30% d.e.) and (2R)-bornane[10,2]sultam (98% d.e.). In the specific case of the N-acryloyl bornane[10,2]sultam, we found evidence for a small predictable negative influence of electronically deficient para-substituted phenyl nitrile oxides on diastereoselectivity (p-Me 2N, 72% d.e.; p-F, 65% d.e.; p-NO2, 60% d.e.). This may be explained by the participation of the more reactive but thermodynamically less stable syn-s-cis conformer in the reaction pathway, given its smaller difference of calculated energies in the corresponding transition states. Such an explanation is further supported by the negative influence of either a polar solvent, stabilizing these more polar transition states (phenyl nitrile oxide in hexane, 76% d.e.; CH2Cl2, 71% d.e.; MeCN, 67% d.e.), or a chelating Lewis acid (MgCl2, 66% d.e.).
