46231-21-4Relevant academic research and scientific papers
Understanding α,β-unsaturated imine formation from amine additions to α,β-unsaturated aldehydes and ketones: An analytical and theoretical investigation
Calow, Adam D. J.,Carbó, Jorge J.,Cid, Jessica,Fernández, Elena,Whiting, Andrew
supporting information, p. 5163 - 5172 (2014/06/23)
A combination of in situ IR spectroscopy (ReactIR) and DFT calculations have been used to understand what factors govern the selectivity in the addition of primary amines to α,β-unsaturated aldehydes and ketones, i.e., 1,2- versus 1,4-addition. It has been found that the 1,2-addition products (α,β-unsaturated imines following addition and elimination) usually predominate for most systems. However, exceptions, such as methyl vinyl ketone, selectively give 1,4-addition products. This has been rationalized by DFT calculations that show that major conformational effects are involved, controlled mainly by steric effects of carbonyl substituents, resulting in a model that provides simple and predictable preparation of α,β- unsaturated imines for in situ utilization in synthesis.
O-benzenedisulfonimide as a reusable brnsted acid catalyst for hetero-michael reactions
Barbero, Margherita,Cadamuro, Silvano,Dughera, Stefano
, p. 758 - 767 (2013/01/15)
The hetero-Michael reactions among various oxygen, sulfur, and nitrogen nucleophiles and ,-unsaturated compounds were carried out in the presence of catalytic amounts of o-benzenedisulfonimide as Brnsted acid organocatalyst. The reaction conditions were very mild, and the yields of target products were good. The catalyst was easily recovered and purified, ready to be used in further reactions. This ability grants economic and ecological advantages. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications to view the free supplemental file.
Dolomite (CaMg(CO3)2) as a recyclable natural catalyst in Henry, Knoevenagel, and Michael reactions
Tamaddon, Fatemeh,Tayefi, Mohammad,Hosseini, Elaheh,Zare, Elham
, p. 36 - 42 (2013/02/22)
Iranian dolomite (CaMg(CO3)2) which consists of double-layered carbonates with Ca2+ and Mg2+ ions was utilized as a heterogeneous base catalyst in the CC, CN, and CS bond forming reactions via the Henry, Knoevenagel, aza-Michael, and thia-Michael transformations under mild conditions in water. Iranian dolomite has been characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Brunauer Emmett Teller (BET) and XRF chemical analysis, while its basic strength was evaluated by following the Hammett indicators procedure. This water-insoluble natural catalyst demonstrated high activity and was reusable.
Novel transformation of α,β-unsaturated aldehydes and ketones into γ-amino alcohols or 1,3-oxazines via a 4 or 5 step, one-pot sequence
Calow, Adam D. J.,Batsanov, Andrei S.,Fernández, Elena,Solé, Cristina,Whiting, Andrew
, p. 11401 - 11403 (2013/01/15)
An efficient, 4-step, one-pot, highly stereoselective route to γ-amino alcohols has been developed via an in situ α,β- unsaturated imine formation, β-boration, reduction (CN) and oxidation (C-B) sequence and especially for certain water-soluble γ-amino alcohols, a further step can be added to directly access the corresponding 1,3-oxazine derivatives.
Supported cobalt complex-catalysed conjugate addition of indoles, amines and thiols to α,β-unsaturated compounds
Rajabi, Fatemeh,Razavi, Sepideh,Luque, Rafael
experimental part, p. 786 - 789 (2010/09/05)
A highly active and reusable supported Co(ii) complex on SBA-15 shows an excellent activity and selectivity to target products in aza- and thia-Michael conjugate additions of indoles, amines and thiols to α,β-unsaturated compounds under solventless mild reaction conditions. The Co-catalyst was also highly reusable and comparably more active than related catalysts in the reaction.
Task-specific ionic-liquid-catalyzed efficient synthesis of indole derivatives under solvent-free conditions
Das, Sudarshan,Rahman, Matiur,Kundu, Dhiman,Majee, Adinath,Hajra, Alakananda
scheme or table, p. 150 - 154 (2010/04/03)
A sulfonic-acid-functionalized ionic liquid is used as a Bronsted acid catalyst for the efficient synthesis of indole derivatives in good-to-high yields at room temperature under solvent-free conditions. The catalyst can be reused for ten consecutive runs without significant loss of activity.
A two-step, formal [4 + 2] approach toward piperidin-4-ones via au catalysis
Cui, Li,Peng, Yu,Zhang, Liming
supporting information; experimental part, p. 8394 - 8395 (2009/10/23)
(Chemical Equation Presented) An efficient, formal [4 + 2] synthesis of synthetically valuable piperidin-4-ones from secondary amines in two steps has been achieved via a key gold catalysis without the purification of tertiary amine intermediates. This reaction is selective toward the less-substituted alkyl group and shows moderate to excellent diastereoselectivities. Its synthetic potential in alkaloid synthesis is demonstratedin a highly diastereoselective synthesis of (±)-cermizine C.
Diastereoselective nickel-catalyzed reductive Aldol cyclizations using diethylzinc as the stoichiometric reductant: Scope and mechanistic insight
Joensuu, Pekka M.,Murray, Gordon J.,Fordyce, Euan A. F.,Luebbers, Thomas,Hon, Wai Lam
, p. 7328 - 7338 (2008/12/22)
In the presence of diethylzinc as a stoichiometric reductant, Ni(acac) 2 functions as an efficient precatalyst for the reductive aldol cyclization of α,β-unsaturated carbonyl compounds tethered to a ketone electrophile through an amide or an ester linkage. The reactions are tolerant of a wide range of substitution at both α,β-unsaturated carbonyl and ketone components and proceed smoothly to furnish β-hydroxylactams and β-hydroxylactones with generally high diastereoselectivities. A series of experiments, including deuterium-labeling studies, was carried out in an attempt to gain some insight into the possible reaction mechanisms that might be operative.
Diastereoselective cobalt-catalyzed alkylative aldol cyclizations using trialkylaluminum reagents
Rudkin, Mairi E.,Joensuu, Pekka M.,MacLachlan, William S.,Hon, Wai Lam
supporting information; experimental part, p. 2939 - 2942 (2009/04/18)
(Chemical Equation Presented) Co(acac)2?·2H2O serves as an effective precatalyst for alkylative aldol cyclizations of ?±,?2-unsaturated amides with ketones using trialkylaluminum reagents. These reactions provide ?2-hydroxylactams containing three contiguous stereocenters with high levels of diastereoselection. ? 2008 American Chemical Society.
Samarium(III) triflate catalyzed conjugate addition of amines to electron-deficient alkenes
Yadav,Ramesh Reddy,Gopal Rao,Narsaiah,Subba Reddy
, p. 3447 - 3450 (2008/09/19)
Amines undergo smooth nucleophilic addition to α,β-unsaturated compounds in the presence of a catalytic amount of samarium(III) triflate at ambient temperature to produce the corresponding β-amino compounds in excellent yields. This method is simple, convenient, and works efficiently under mild conditions. Georg Thieme Verlag Stuttgart.
