- In/InCl3-mediated cross-coupling reactions of methyl vinyl ketone with benzaldehyde in aqueous media
-
(matrix presented) Various β,γ-unsaturated ketones were successfully prepared by cross-coupling reactions of methyl vinyl ketone (MVK) with benzaldehydes mediated by In/InCl3 in aqueous media.
- Kang, Soyeon,Jang, Taeg-Su,Keum, Gyochang,Kang, Soon Bang,Han, So-Yeop,Kim, Youseung
-
-
Read Online
- Selective Pinacol-Coupling Reaction using a Continuous Flow System
-
The first continuous flow pinacol coupling reaction of carbonyl compounds was successfully achieved within only 2 min during a single pass through a cartridge filled with zinc(0). The optimized method allowed the efficient production of gram-scale value-added compounds with high productivity. The developed methodology is efficient for aromatic or α,β-unsaturated aldehydes but gives moderate results for more stable acetophenone derivatives. Moreover, the flow method displayed better results in terms of yield and selectivity in comparison to the corresponding batch methodology.
- Sotto, Nicolas,Cazorla, Clément,Villette, Carole,Billamboz, Muriel,Len, Christophe
-
p. 11065 - 11071
(2016/11/28)
-
- Selective Pinacol Coupling on Regeneratable Supported Acids in Sole Water
-
Efficient pinacol coupling was developed in sole water, using a reusable heterogeneous supported acid source and zinc as cheap available metal source. This medium can be easily regenerated up to 10-fold without loss of activity. Moreover, supported acids enhance the selectivity of the pinacol coupling reaction compared with homogeneous acids.
- Sotto, Nicolas,Billamboz, Muriel,Chevrin-Villette, Carole,Len, Christophe
-
p. 6375 - 6380
(2015/06/30)
-
- First pinacol coupling in emulsified water: Key role of surfactant and impact of alternative activation technologies
-
For the first time, the influence of surfactants on the radical pinacol coupling reaction is investigated. The rate and selectivity of this reductive C-C coupling are compared under three different activation technologies: thermal activation, microwave irradiation, and sonication. The use of IgepalCO520, a neutral surfactant, led to the successful conversion of aromatic or α,β-unsaturated aliphatic carbonyl compounds in moderate to excellent yield (55-90 %). An insight on the potential mechanism involved in the reaction is also proposed, based on microscopic observations and particle size measurement.
- Billamboz, Muriel,Len, Christophe
-
p. 1664 - 1675
(2015/06/02)
-
- Mg/Triethylammonium formate: A useful system for reductive dimerization of araldehydes into pinacols; Nitroarenes into azoarenes and azoarenes into hydrazoarenes
-
Studies are reported which describes the effectiveness of triethylammonium formate in the presence of magnesium for the efficient intermolecular pinacol coupling using MeOH as solvent, Various aromatic carbonyls underwent smooth reductive coupling to give the corresponding I ,2-diols. A series of azo compounds were obtained by the reductive coupling of nitroaromatics while azo compounds were reduced to the corresponding hydrazoarenes by this system. There was no adverse effect on the other reducible and hydrogenolysable groups such as ether linkage, hydroxy and halogens. The reactions are clean, high yielding and inexpensive. All the reactions proceeded smoothly at ambient temperature.
- Pamar, M. Geeta,Govender,Muthusamy,Krause, Ruiw M.,Nanjundaswamy
-
p. 969 - 974
(2014/03/21)
-
- A new Yb3+-catalyzed pinacol and imine-coupling reaction
-
Ytterbium triflate, Yb(OTf)3, catalyzes the intermolecular reductive homocouplings of imines, aldehydes, and ketones at loadings of 5 mol % in the presence of Mg and Me3SiCl to give isolated yields of up to 95%. Diastereoselectivity of up to 4/96 (dl/meso) is achieved for aromatic aldehydes, up to 100% dl for aliphatic aldehydes, and 100% dl for an intramolecular imine coupling.
- Aspinall, Helen C.,Greeves, Nicholas,Hin, Shane Lo Fan
-
experimental part
p. 1558 - 1561
(2010/06/13)
-
- Pinacol coupling reaction of aromatic aldehydes mediated by aqueous vanadium(II) solution under ultrasound irradiation
-
Pinacol coupling of aromatic aldehydes by aqueous vanadium(II) solution under ultrasound irradiation at room temperature can lead to the corresponding pinacols in 54-93% yields within 15-30 min. Copyright Taylor & Francis, Inc.
- Wang, Shu-Xiang,Wang, Ke,Li, Ji-Tai
-
p. 2387 - 2394
(2007/10/03)
-
- Pinacol coupling reaction of beta-halo-alpha,beta-unsaturated aldehydes promoted by TiI4.
-
The pinacol reaction of beta-halogenated alpha,beta-unsaturated aldehydes was promoted by titanium tetraiodide to give coupling products in good yields with high dl-selectivity. Subsequent reduction with H(2)/Pd-C gave saturated vic-diols in good yields. Heck coupling reaction enabled the displacement of halogens with vinyl groups without the loss of stereochemical integrities. [reaction: see text]
- Shimizu, Makoto,Goto, Hiroshi,Hayakawa, Ryuuichirou
-
p. 4097 - 4099
(2007/10/03)
-
- Pinacol coupling of aromatic aldehydes and ketones using Zn-ZnCl2 under ultrasound
-
The coupling reaction of aromatic aldehydes and ketones leading to pinacols has been carried out using Zn-ZnCl2 in 50% aq. THF under ultrasound in 5-77% yield.
- Zang, Hong-Jun,Li, Ji-Tai,Ning, Ning,Wei, Na,Li, Tong-Shuang
-
p. 1078 - 1080
(2007/10/03)
-
- Pinacol coupling of aromatic aldehydes and ketones using magnesium in aqueous ammonium chloride under ultrasound
-
The pinacol coupling reaction of aromatic aldehydes and ketones was performed in 8-95% yield with magnesium in 0.1 M aqueous NH4C1 under ultrasound irradiation at r.t. for 3 h.
- Li, Ji-Tai,Bian, Yan-Jiang,Zang, Hong-Jun,Li, Tong-Shuang
-
p. 547 - 551
(2007/10/03)
-
- Indium-catalyzed reductive coupling of aromatic carbonyl compounds and imines in the presence of aluminum and chlorosilanes
-
Reductive homocoupling of aromatic aldehydes, ketones, and imines has been achieved in tetrahydrofuran (THF) at room temperature using a catalytic amount of InCl3 (0.5-3.0 mol %) under a nitrogen atmosphere in the presence of chlorotrimethylsilane (TMSCl) and aluminum metal (Al) to provide the corresponding 1,2-diols and 1,2-diamines, respectively, in good to moderate yields. Other indium compounds such as In(NO3)3, cyclopentadienylindium, and indium metal have also been revealed to be effective as catalysts. The catalytic effect of the indium compound is remarkable, and, thus, without it, no reaction occurs in the case of aromatic aldehydes and aldimines, and an induction period is quite long in the case of aromatic ketones. Without either TMSCl or Al, no reaction proceeds even in the presence of the catalyst. Unfortunately, the diastereoselectivity of the products (dl and meso) is not high. Although the precise reaction scheme is not yet clear, we tentatively propose that a redox-active In-Al alloy might be formed on the surface of aluminum in the presence of TMSCl, and an electron transfer from the alloy to substrate might occur.
- Ohtaka, Seiji
-
p. 309 - 316
(2007/10/03)
-
- Efficient diastereoselective pinacol coupling reaction of aliphatic and aromatic aldehydes by using newly utilized low valent titanium bromide and iodide species
-
Reductive coupling reaction of aromatic and aliphatic aldehydes proceeded under mild conditions to give the corresponding pinacols in moderate to high yields and DL-diastereoselectivities by using combinations of either low valent titanium(II) bromide and copper or titanium(IV) iodide and copper in a mixed solvent of dichloromethane and pivalonitrile. In the case of using titanium(IV) iodide and copper, pinacols were obtained in good to high yields with moderate to high diastereoselectivities irrespective of the number of substitutuents at α-position of aliphatic aldehydes.
- Mukaiyama, Teruaki,Yoshimura, Naritoshi,Igarashi, Koji,Kagayama, Akifumi
-
p. 2499 - 2506
(2007/10/03)
-
- Efficient diastereoselective pinacol reaction of aliphatic and aromatic aldehydes by combined use of newly utilized titanium(II) bromide and copper
-
Newly utilized low-valent titanium reductant, titanium(II) bromide, was conveniently prepared by treating titanium(IV) bromide with hexamethyldisilane. The pinacol reaction of aromatic and aliphatic aldehydes including primary aldehydes proceeded smoothly in dichloromethane-pivalonitrile at temperatures ranging from -23 to 0 °C by the combined use of soluble titanium(II) bromide and copper to give 1,2-diols in good to high yields with good to high dl-selectivities.
- Mukaiyama, Teruaki,Kagayama, Akifumi,Igarashi, Koji
-
p. 336 - 337
(2007/10/03)
-
- Selective reduction of organic compounds with indium hydride reagents
-
Three indium hydride reagents (LiInH4, LiPhInH3, and LiPh2InH2) were prepared and successfully used for the selective reduction of various organic compounds.
- Yamada, Masafumi,Tanaka, Koji,Araki, Shuki,Butsugan, Yasuo
-
p. 3169 - 3172
(2007/10/02)
-
