1075-77-0Relevant articles and documents
Secondary amine-catalyzed [3 + 3] benzannulation to access polysubstituted benzenes through iminium activation
Jiang, Lin,Li, Hang,Zhou, Jiang-Feng,Yuan, Ming-Wei,Li, Hong-Li,Chuan, Yong-Ming,Yuan, Ming-Long
, p. 336 - 343 (2018)
An organocatalytic [3 + 3] benzannulation to access polysubstituted benzenes from readily available α,β-unsaturated aldehydes and 1,3-bis(phenylsulfonyl)propene or 4-sulfonylcrotonates is described. The key reaction step is considered to be the iminium ac
Modular synthesis of (E)-cinnamaldehydes directly from allylarenes via a metal-free DDQ-mediated oxidative process
Xu, Ting-Ting,Jiang, Tao-Shan,Han, Xiao-Lan,Xu, Yuan-Hong,Qiao, Jin-Ping
, p. 5350 - 5358 (2018)
An efficient synthesis of (E)-cinnamaldehydes by a metal-free DDQ-mediated oxidative transformation of allylarenes was developed. The protocol provides a practical method to prepare diverse (E)-cinnamaldehydes with broad functional group tolerance in good to excellent yields, including easy access to natural products randainal and geranyloxy sinapyl aldehyde from plant extracts. Finally, the mechanism of a single-electron transfer process was proposed.
Substrate-selective mechanisms in biocatalysis demonstrated with a versatile and efficient aldolase antibody
Shulman, Hagit,Keinan, Ehud
, p. 1745 - 1750 (1999)
A structure-activity relationship study with a series of aldol substrates shows that the mechanism of the antibody 38C2-catalyzed retrograde aldol reaction depends on the nature of the substrate with electron-deficient substrates an early deprotonation precedes the C-C bond cleavage while with electron-rich substrates the catalytic mechanism involves an initial C-C bond cleavage leading to a positively charged intermediate.
Arenediazonium o-benzenedisulfonimides as efficient reagents for Heck-type arylation reactions
Artuso, Emma,Barbero, Margherita,Degani, Iacopo,Dughera, Stefano,Fochi, Rita
, p. 3146 - 3157 (2006)
Arenediazonium o-benzenedisulfonimides can be used as new and efficient reagents for Heck-type arylation reactions of some common substrates containing C-C multiple bonds, namely ethyl acrylate, acrylic acid, acroleyne, styrene and cyclopentene. The reactions were carried out in an organic solvent, in the presence of Pd(OAc)2 as pre-catalyst, and gave rise to arylated products, for example, ethyl cinnamates, cinnamic acids, cinnamic aldehydes and stilbenes, possessing an (E)-configuration, and 1-arylcyclopentenes, in good to excellent yields. It is noteworthy that all the reactions led to the recovery, in greater than 80% yield, of o-benzenedisulfonimide, recyclable for the preparation of other diazonium salts.
Self pH regulated iron(II) catalyst for radical free oxidation of benzyl alcohols
Das, Biraj,Baruah, Manash J.,Sharma, Mukesh,Sarma, Bipul,Karunakar, Galla V.,Satyanarayana, Lanka,Roy, Subhasish,Bhattacharyya, Pradip K.,Borah, Kamala Kanta,Bania, Kusum K.
, (2020)
Selective oxidation of various aromatic benzyl alcohols to benzaldehydes was found to be catalyzed with 90% conversion and 99% selectivity by an iron (II) catalyst herein designated as Fe-DDPA [DDPA = 3′-disulfanediyldipropionic acid]. The Fe-DDPA catalyst was prepared by a small loading of FeCl2 into a 2D sheet formed by the supramolecular assembling of DDPA. From both solid and liquid state nuclear magnetic resonance (NMR) spectroscopic study it was evident for the stabilization of the Fe(II) center through Fe-S interaction with the disulfide (S-S) unit of DDPA. DDPA was found to serve as an excellent support to maintain a pH that was required for a radical free oxidation of benzyl alcohol to aldehydes. The catalytic oxidation of benzyl alcohols was found to occur with excellent conversion and selectivity in acetonitrile (CH3CN) solvent in comparison to various other solvents. From various spectroscopic studies viz UV-vis, FT-IR and ESI-MS it was ascertained that the CH3CN interacted with Fe-DDPA to form a [(DDPA)2Fe(CH3CN)2]2+ species which then reacted with H2O2 to form an intermediate Fe-hydroxoperoxo, FeIII-OOH species. The Fe-OOH further got oxidized to the active FeIV=O species and was responsible for bringing the high selectivity in the oxidation reaction. The generation of highly unstable Fe-OOH species was further confirmed by electrochemical study, UV–vis, Raman and ESR spectroscopic analysis.
An improved general method for palladium catalyzed alkenylations and alkynylations of aryl halides under microwave conditions
Togninelli, Andrea,Gevariya, Harsukh,Alongi, Maddalena,Botta, Maurizio
, p. 4801 - 4803 (2007)
Palladium catalyzed facile method for alkenylation and alkynylation of arylhalides in good to excellent yield under microwave condition is reported.
Crossed Regio- and Enantioselective Iron-Catalyzed [4+2]-Cycloadditions of Unactivated Dienes
Braconi, Elena,Cramer, Nicolai
supporting information, (2021/12/22)
The cyclohexene motif is ubiquitous in nature and specialty chemicals. A straightforward selective access to chiral cyclohexenes from unactivated dienes and dienophiles is not feasible by classical Diels–Alder reaction and constitutes an unsolved syntheti
Enantioselective Organocatalytic Synthesis of 1,2,3-Trisubstituted Cyclopentanes
?otolová, Martina,Kamlar, Martin,Reme?, Marek,Géant, Pierre-Yves,Císa?ová, Ivana,?tícha, Martin,Vesely, Jan
, p. 5080 - 5089 (2021/09/30)
An organocatalytic asymmetric domino Michael/α-alkylation reaction between enals and non-stabilized alkyl halides has been developed. Chiral secondary amine catalyzed cyclization reaction of 1-bromo-3-nitropropane with α,β-unsaturated aldehydes provides 1,2,3-trisubstituted cyclopentane carbaldehydes with high diastereo- (dr up to 8 : 1) and enantioselectivities (ee up to 96 %).
