76691-98-0Relevant academic research and scientific papers
Reactivities of Nitrenes Generated by Photolysis of 2-(ω-Phenylalkyl)phenyl Azides
Murata, Shigeru,Yoshidome, Ryuichi,Satoh, Youji,Kato, Noriyasu,Tomioka, Hideo
, p. 1428 - 1434 (2007/10/02)
In order to investigate the reactivity of a photolytically generated arylnitrene with an intramolecular CH bond, the photochemistry of 2-(ω-phenylalkyl)phenyl azides (1a-d) was examined.Irradiation of 1 in solution revealed that the insertion of the nitrene into an adjacent CH bond to give cyclic compounds 4 and 5 occurs favorably only when a reactive CH bond, such as benzylic, is located close to the nitrenic center.This process can compete with the formation of products derived from triplet nitrene, but not with the capture of didehydroazepine by DEA.On the other hand, irradiation of 1b in an Ar matrix at 12 K gave a mixture of the CH insertion product 4b and the didehydroazepine 15.The origin of the difference in reactivity of the nitrene observed in solutions and in matrix, and the spin state of the nitrene involved in the CH insertion reaction, are discussed.
Phase-Transfer-Catalyzed Gomberg-Bachmann Synthesis of Unsymmetrical Biarenes: A Survey of Catalysts and Substrates
Beadle, James R.,Korzeniowsky, Stephen H.,Rosenberg, David E.,Garcia-Slanga, Blanche J.,Gokel, George W.
, p. 1594 - 1603 (2007/10/02)
Two problems have hindered the Gomberg-Bachmann (GB) and Pschorr reactions of arenediazonium cations: the instability of the arenediazonium salts and side reactions.Arenediazonium tetrafluoroborate and hexafluorophosphate salts can be prepared in high yield and purity and can be stored safely.Unfortunately, these salts are insoluble in most nonpolar organic solvents.Crown ether complexation or other phase-transfer (pt) catalytic methodology can ameliorate this situation, and reactions conducted by the approaches outlined herein often afforded coupling or cyclization products in high yield and corresponding purity.The use of crown ethers, quarternary 'onium salts, lipophilic carboxylic acid salts, and even the polar cosolvent acetonitrile increase the utility of the ptGB reaction dramatically.Sixty examples of couplings are reported along with an assessment of selectivities.A number of examples are also presented of phase-transfer-type Pschorr cyclizations.In the latter case, the use of potassium superoxide, KO2, is introduced to suppress indazole formation.
