10409-47-9Relevant articles and documents
A mild and efficient procedure for α-bromination of ketones using N-bromosuccinimide catalysed by ammonium acetate
Tanemura, Kiyoshi,Suzuki, Tsuneo,Nishida, Yoko,Satsumabayashi, Koko,Horaguchi, Takaaki
, p. 470 - 471 (2004)
Cyclic ketones reacted with N-bromosuccinimide (NBS) catalysed by NH 4OAc in Et2O at 25°C to give the corresponding α-brominated ketones in good yields, while acyclic ketones were efficiently brominated in CCl4 at 80°C.
A New and Highly Effectiwe Aldol Synthesis
Maruoka, Keiji,Hashimoto, Shinsuke,Kitagawa, Yoshizo,Yamamoto, Hisashi,Nozaki, Hitosi
, p. 3301 - 3307 (1980)
A new approach has been demonstrated for the regiospecific aldol synthesis by the simultaneous addition of α-halo carbonyl derivatives and aldehydes or ketones to a suspension of diethylaluminium chloride and zinc in tetrahydrofuran at low temperature.This technique is also employable under mild conditions for the Reformatsky reaction to give β-hydroxy esters in excellent yield.One of the unique synthetic applications of this process is illustrated by the intramolecular cyclization of α-bromo esters of ω-hydroxy aldehyde,which produces macrolides, an important cla ss of compounds in the antibiotic field.
Cobalt-Catalyzed Regioselective Olefin Isomerization under Kinetic Control
Liu, Xufang,Zhang, Wei,Wang, Yujie,Zhang, Ze-Xin,Jiao, Lei,Liu, Qiang
supporting information, p. 6873 - 6882 (2018/05/30)
Olefin isomerization is a significant transformation in organic synthesis, which provides a convenient synthetic route for internal olefins and remote functionalization processes. The selectivity of an olefin isomerization process is often thermodynamically controlled. Thus, to achieve selectivity under kinetic control is very challenging. Herein, we report a novel cobalt-catalyzed regioselective olefin isomerization reaction. By taking the advantage of fine-tunable NNP-pincer ligand structures, this catalytic system features high kinetic control of regioselectivity. This mild catalytic system enables the isomerization of 1,1-disubstituted olefins bearing a wide range of functional groups in excellent yields and regioselectivity. The synthetic utility of this transformation was highlighted by the highly selective preparation of a key intermediate for the total synthesis of minfiensine. Moreover, a new strategy was developed to realize the selective monoisomerization of 1-alkenes to 2-alkenes dictated by installing substituents on the γ-position of the double bonds. Mechanistic studies supported that the in situ generated Co-H species underwent migratory insertion of double bond/β-H elimination sequence to afford the isomerization product. The less hindered olefin products were always preferred in this cobalt-catalyzed olefin isomerization due to an effective ligand control of the regioselectivity for the β-H elimination step.
Intramolecular carbonickelation of alkenes
Lhermet, Rudy,Durandetti, Muriel,Maddaluno, Jacques
supporting information, p. 710 - 716 (2013/06/05)
The efficiency of the intramolecular carbonickelation of substituted allylic ethers and amines has been studied to evaluate the influence of the groups borne by the double bond on this cyclization. The results show that when this reaction takes place, it affords only the 5-exo-trig cyclization products, viz. dihydrobenzofurans or indoles. Depending on the tethered heteroatom (O or N), the outcome of the cyclization differs. While allylic ethers are relatively poor substrates that undergo a side elimination and need an intracyclic double bond to proceed, allylic amines react well and afford indoline and indole derivatives. Finally, the synthesis of the trinuclear ACE core of a morphine-like skeleton was achieved by using NiBr2bipy catalysis.
