Copper-catalyzed enantioselective conjugate reduction of α,β-unsaturated esters with chiral phenol–carbene ligands

• Shohei Mimura,
• Sho Mizushima,
• Yohei Shimizu and
• Masaya Sawamura

Beilstein J. Org. Chem. 2020, 16, 537–543, doi:10.3762/bjoc.16.50

• hydride species B. This transmetalation adds the silyl group to the phenoxy oxygen atom of the NHC ligand. The coordination of an α,β-unsaturated carbonyl compound 1 to the copper atom occurs in such a way that the bulky O-silyl group of the copper catalyst can avoid steric repulsions with the

Copper-promoted/copper-catalyzed trifluoromethylselenolation reactions

• Clément Ghiazza and
• Anis Tlili

Beilstein J. Org. Chem. 2020, 16, 305–316, doi:10.3762/bjoc.16.30

• in the reaction, resulting from an oxidative addition of the trifluoromethylselenolated copper(I) complex to the α-brominated unsaturated carbonyl compound. Afterwards, a reductive elimination would take place to afford the α-trifluoromethylselenylated α,β-unsaturated carbonyl compound and copper(I

Visible-light-induced, Ir-catalyzed reactions of N-methyl-N-((trimethylsilyl)methyl)aniline with cyclic α,β-unsaturated carbonyl compounds

• Dominik Lenhart and
• Thorsten Bach

Beilstein J. Org. Chem. 2014, 10, 890–896, doi:10.3762/bjoc.10.86

• 7 operates [54][55][56][57][58]. Oxidation of the aniline and loss of the trimethylsilyl group leads to an α-aminomethyl radical, which adds to the cyclic α,β-unsaturated carbonyl compound (Scheme 8). The intermediate radical A can undergo immediate reduction presumably by concomitant oxidation of

• could occur by hydrogen transfer to the starting material, i.e., the α,β-unsaturated carbonyl compound [39], which would explain why the yields never exceeded 50%. Upon hydrogen transfer the α,β-unsaturated carbonyl compound would give a cyclic α-acyl radical, which would be capable to re-oxidize the

AgOTf-catalyzed one-pot reactions of 2-alkynylbenzaldoximes with α,β-unsaturated carbonyl compounds

• Qiuping Ding,
• Dan Wang,
• Puying Luo,
• Meiling Liu,
• Shouzhi Pu and
• Liyun Zhou

Beilstein J. Org. Chem. 2013, 9, 1949–1956, doi:10.3762/bjoc.9.231

• excellent yields. Keywords: 2-alkynylbenzaldoxime; cyclization; 2-(isoquinolin-1-yl)ethanol; rearrangement; α,β-unsaturated carbonyl compound; Introduction One-pot combinations of multi-catalysis and multi-component cascade reactions [1][2][3][4][5][6], in which several bond-forming steps take place in a

• progress in this aspect. Wu and co-workers described an efficient three-component reaction of a 2-alkynylbenzaldoxime and an α,β-unsaturated carbonyl compound with bromine or iodine monochloride under mild conditions, which generates the 1-alkylated isoquinolines in good to excellent yields [36]. Wu and co

• a 1,3-dipolar cycloaddition with α,β-unsaturated carbonyl compound 2 leading to 2,10b-dihydro-1H-isoxazolo[3,2-a]isoquinoline intermediate B [44][45], which may then suffer a rearrangement or fragmentation resulting in compound 3 (Scheme 1) [35][36][38][42]. To demonstrate the feasibility of this

One-pot synthesis of novel 1H-pyrimido[4,5-c][1,2]diazepines and pyrazolo[3,4-d]pyrimidines

• Dipak Prajapati,
• Partha P. Baruah,
• Baikuntha J. Gogoi and
• Jagir S. Sandhu

Beilstein J. Org. Chem. 2006, 2, No. 5, doi:10.1186/1860-5397-2-5

• discussions The synthesis of pyrimido [4,5-c][1,2]diazepine-6,8-dione 3a was accomplished by reacting equimolar quantities of 1,3-dimethyl-6-hydrazino uracil 1 and α,β-unsaturated carbonyl compound 2a in ethanol under reflux for 3 h (monitored by TLC). The suspension of 6-hydrazino uracil 1 first disappeared