37442-45-8Relevant articles and documents
Reevaluation of the mechanism of the Baylis-Hillman reaction: Implications for asymmetric catalysis
Aggarwal, Varinder K.,Fulford, Sarah Y.,Lloyd-Jones, Guy C.
, p. 1706 - 1708 (2005)
(Chemical Equation Presented) One step beyond: Proton transfer (step 3, see scheme), not C-C bond formation (step 2) as previously thought, is the rate-limiting step (RLS) in the initial stage of the Baylis-Hillman reaction, which involves the amine-catal
Efficient Baylis-Hillman reaction via a 1,4-diazabicyclo[2.2.2]octane-based ionic catalyst
Cai, Yueqin,Liu, Ye,Gao, Guohua
, p. 1163 - 1166 (2007)
A novel ionic catalyst, 1-butyl-4-aza-1-azoniabicyclo[2.2.2]octane chloride based on 1,4-diazabicyclo[2.2.2]octane was synthesized and applied in the Baylis-Hillman reaction, which occurred readily at room temperature to afford the corresponding adducts i
Can Heteroarenes/Arenes Be Hydrogenated Over Catalytic Pd/C Under Ambient Conditions?
Tanaka, Nao,Usuki, Toyonobu
supporting information, p. 5514 - 5522 (2020/07/24)
Hydrogenation of over a dozen aromatic compounds, including both heteroarenes and arenes, over palladium on carbon (Pd/C, 1–100 molpercent) with H2-balloon pressure at room temperature is reported. Analyses using pyridine as a model substrate revealed that acetic acid was the best solvent, as using only 1 molpercent Pd/C provided piperidine quantitatively. Substrate scope analysis and density functional theory calculations indicated that reaction rates are highly dependent on frontier molecular orbital characteristics and the steric bulkiness of substituents. Moreover, the established method was used for the concise synthesis of the anti-Alzheimer drug donepezil (Aricept?).
Silver/palladium relay catalyzed 1,3-dipole annulation/allylation reactions to access fully substituted allyl imidazolidines
Han, Ruiping,Ding, Yue,Jin, Xueke,Li, Er-Qing
supporting information, p. 646 - 649 (2020/02/11)
A silver/palladium relay catalyzed 1,3-dipole annulation/allylation reaction of iminoesters and Baylis-Hillman acetates for the construction of fully substituted allyl imidazolidines is reported. The reaction of both iminoesters and Baylis-Hillman acetate
Enantioselective Lewis base catalyzed phosphonyldifluoromethylation of allylic fluorides using a: C -silyl latent pronucleophile
Zi, You,Lange, Markus,Vilotijevic, Ivan
supporting information, p. 5689 - 5692 (2020/06/19)
The first enantioselective phosphonyldifluoromethylation is enabled by the use of diethyl (difluoro(trimethylsilyl)-methyl)phosphonate reagent as a latent pronucleophile in the Lewis base catalyzed substitution of allylic fluorides. The reaction proceeds
On the development of a nucleophilic methylthiolation methodology
Carvalho, Bernardo Basbaum Portinho De Puga,Amaral, Adriane Antonia Pereira,De Castro, Pedro P?ssa,Ferreira, Fernanda Cerqueira Moreira,Horta, Bruno Araújo Cautiero,Amarante, Giovanni Wilson
, p. 5420 - 5426 (2020/08/03)
Methylthiolation reactions are usually explored to access organosulfur compounds using methanethiol, an extremely flammable and toxic compound. Herein, methylthiomethyl esters were successfully applied as novel methylthiolation reagents in a low cost, transition-metal-free methodology. These reagents allowed the methylthiolation of a wide scope of chalcones, acyl ester derivatives and Morita-Baylis-Hillman acetates with good group tolerance, affording the methylthiolated products in moderate to excellent yields. The reaction mechanism was investigated through several control experiments, as well as by theoretical calculations employing Density Functional Theory. The results strongly support that a sulfurane and a sulfonium ylide appear as key intermediates and that a Pummerer type rearrangement is also crucial for the formation of this novel reagent. Furthermore, the methylthiolation mechanism is likely to proceed through the nucleophilic attack of the reagent, followed by an entropically favoured step involving the acetate attack to the positively charged species, then releasing the product. This journal is
Azidophosphonium salt-directed chemoselective synthesis of (E)/(Z)-cinnamyl-1H-Triazoles and regiospecific access to bromomethylcoumarins from Morita-Baylis-Hillman adducts
Karthikeyan, Soundararajan,Shobana, Radha Krishnan,Subimol, Kamarajapurathu Raju,Helen Ratna Monica,Kumar, Ayyanoth Karthik Krishna
, p. 1579 - 1587 (2020/09/16)
The direct transformation of Morita-Baylis-Hillman (MBH) adducts into molecules of interest is a crucial process wherein allylic hydroxy-protected or halogenated MBH adducts are commonly preferred. Herein, we report an azidophosphonium salt (AzPS)-catalys
Unprecedented E-stereoselectivity on the sigmatropic Hurd-Claisen rearrangement of Morita-Baylis-Hillman adducts: A joint experimental-theoretical study
Silva, Vinicius Sobral,Tolentino, Terezinha Alves,Rodrigues, Tiago Costa Alves Fontoura,Santos, Fernanda Ferrari Martins,Machado, Daniel Francisco Scalabrini,Silva, Wender Alves,Oliveira, Heibbe Cristhian Benedito De,Machado, Angelo Henrique Lira
, p. 4498 - 4511 (2019/05/17)
Herein we report the first systematic investigation of the tandem mercury(ii) catalysed transvinylation/Hurd-Claisen rearrangement of MBH adducts derived from alkyl acrylates. This is the first report of E-selectivity for MBH adducts with alkyl side chain
Enantioselective dearomative [3+2] cycloaddition of 2-nitrobenzofurans with aldehyde-derived Morita-Baylis-Hillman carbonates
Yang, Xin-He,Li, Jian-Ping,Wang, Dong-Chao,Xie, Ming-Sheng,Qu, Gui-Rong,Guo, Hai-Ming
supporting information, p. 9144 - 9147 (2019/08/07)
The phosphine-catalyzed asymmetric dearomative [3+2] cycloaddition of 2-nitrobenzofurans with aldehyde-derived Morita-Baylis-Hillman (MBH) carbonates or allenoate was developed. The reaction with MBH carbonates resulted in a series of cyclopentabenzofurans containing three contiguous stereocenters with good to high yields, diastereoselectivities and enantioselectivities. The use of allenoate also gave the target product with moderate enantioselectivity.
A Hydrazine Insertion Route to N′-Alkyl Benzohydrazides by an Unexpected Carbon-Carbon Bond Cleavage
Jha, Ajit Kumar,Kumari, Rajkiran,Easwar, Srinivasan
supporting information, p. 8191 - 8195 (2019/10/16)
A serendipitous carbon-carbon bond cleavage in the reaction of benzoyl acrylates, derived from Morita-Baylis-Hillman adducts, with hydrazines delivered new N′,N′-disubstituted benzohydrazides. The reaction features a regioselective formation of two carbon
