79422-40-5Relevant academic research and scientific papers
Intramolecular biaryl coupling reaction of benzyl benzoate and phenyl benzoate derivatives, and its application to the formal synthesis of (-)-steganone
Takeda, Shigemitsu,Abe, Hitoshi,Takeuchi, Yasuo,Harayama, Takashi
, p. 396 - 408 (2007/10/03)
Construction of the biaryl moiety of stegane and related compounds through an intramolecular biaryl coupling reaction is described. Undesired products were obtained by the intramolecular coupling reaction of benzyl benzoates (8, 13, and 14) because of the
An attempt for biaryl coupling reaction of benzyl benzoate derivatives under Ullmann conditions
Abe, Hitoshi,Takeda, Shigemitsu,Takeuchi, Yasuo,Harayama, Takashi
, p. 521 - 528 (2007/10/03)
The biaryl coupling reaction of benzyl benzoate derivatives (3) and (4) was examined with copper(0) reagent. A dimerized product (9) was mainly obtained whereas the desired intramolecularly coupled product (11) was not detected when 3 was employed as the
Reaction of Aryl and Vinyl Halides with Zerovalent Nickel-Preparative Aspects and the Synthesis of Alnusone
Semmelhack, M.F.,Helquist, Paul,Jones, L.D.,Keller, Leonard,Mendelson L.,et al.
, p. 6460 - 6471 (2007/10/02)
Zerovalent nickel complexes such as bis(1,5-cyclooctadiene)nickel and tetrakis(triphenylphosphine)nickel react rapidly with aryl and vinyl halides to produce the symmetrical coupling products, a low-temperature analogue of the Ullman reaction.The reaction proceeds through oxidative addition of the organic halide to Ni(0), and the reactivity of the Ni(II)intermediates has been examined.Arylnickel halide complexes decompose rapidly to biaryls in DMF.The coupling of simple vinyl halides proceeds with isomerization of the double bond but 3-haloacrylates give efficient co upling with retention of geometry.Cyclizations to form ortho-bridged biaryls are efficient in simple cases (6-, 7-, 8-, 9-, 10-, and 14-membered rings) but fail with an ortho-disubstituted case.The 13-membered meta-bridged cyclic biphenyl, alnusone, is prepared efficiently with the crucial aryl halide coupling to form the ring proceeding in 50percent yield.A side reaction promoted by the presence of protons and with certain ortho-substituted aryl halides is reduction of the aryl halide to the arene.This process can be enhanced by deliberate addition of acid during reaction with Ni(0) and a series of aryl halides underwent succesful reduction.
