19836-62-5Relevant academic research and scientific papers
One-pot synthesis of analogues of precocenes and isoprenyl-chromenes
Lamcharfi,Menguy,Zamarlik
, p. 3019 - 3028 (1993)
A convenient one-pot synthesis of chromenes is described. It results from simultaneous addition and cyclization of differently parasubstituted monophenols and aldehydes of isoprenic type (5 or 10 carbons), heated for several hours in refluxing pyridine (or 4-methylpyridine).
Microwave assisted synthesis and anti microbial activity of 2,2-dimethyl chromenes
Suresh Babu,China Raju,Praveen,Hara Kishore,Suryanarayana Murty,Madhusudana Rao
, p. 519 - 526 (2003)
2,2-Dimethyl chromenes (1b-9b) were prepared from corresponding propargyl ethers (1a-9a) under microwave conditions in high yields and anti microbial activity of compounds (6b & 7b) is reported.
ReCl(CO)5-catalyzed cyclocondensation of phenols with 2-methyl-3-butyn-2-ol to afford 2,2-dimethyl-2H-chromenes
Zeng, Hanxiang,Ju, Jia,Hua, Ruimao
, p. 3926 - 3928 (2011)
A direct one-pot route for the synthesis of 2,2-dimethyl-2H-chromenes by Re(CO)5Cl-catalyzed cyclocondensation of phenols with 2-methyl-3-butyn-2-ol has been developed. The easy availability of starting materials, mild reaction conditions, high
An experimental attempt to identify a moving molecular moiety in a solvent matrix
Goto, Yoshitaka,Sugita, Keijiro,Takahashi, Toru,Ohga, Yasushi,Asano, Tsutomu
, p. 618 - 619 (2003)
It was experimentally demonstrated that microscopic friction between a reactant molecule and the surrounding solvent during a unimolecular structural change increased with increasing bulkiness of substituents and it is suggested that this dependence can be used to identify a moving molecular moiety in the reactant inside of a solvation shell.
A novel method for the synthesis of substituted benzochromenes by ethylenediamine diacetate-catalyzed cyclizations of naphthalenols to α,β-unsaturated aldehydes. Concise synthesis of the natural products lapachenole, dihydrolapachenole, and mollugin
Yong, Rok Lee,Yun, Mi Kim
, p. 2401 - 2413 (2007)
A new synthetic route for biologically interesting benzochromenes was developed starting from naphthalenols and α,β-unsaturated aldehydes in the presence of ethylenediamine diacetate. This methodology was applied for the total synthesis of the biologicall
A new application of high-viscosity kinetics. An attempt to identify a site of solvent reorganizations around a reactant
Sugita, Keijiro,Goto, Yoshitaka,Ono, Mikiko,Yamashita, Kazumi,Hayase, Kayoko,Takahashi, Toru,Ohga, Yasushi,Asano, Tsutomu
, p. 1803 - 1806 (2004)
Thermal fading of a colored species photochemically generated from so-called chromenes was kinetically studied in highly viscous media. The reaction was retarded by an increase in viscosity at viscosities higher than 102 Pas. We propose to use substituent dependence of this retarding effect as a tool to identify the main site of solvent reorganizations around the reactant molecule in the activation step.
Pd-Catalyzed Formal [3 + 3] Heteroannulation of Allylic gem-Diacetates: Synthesis of Chromene-Based Natural Products and Exploration of Photochromic Properties
Kumar, Prashant,Kumar, Pravesh,Venkataramani, Sugumar,Ramasastry
, p. 963 - 970 (2022/01/19)
Palladium-catalyzed allylic alkylation reactions of allylic gem-diacetates are rarely explored. This work unveils an unusual chemical reactivity pattern of allylic gem-diacetates and establishes them as new prototypes to synthesize complex benzo[f]chromene systems. Under the reaction conditions, the diacetates behave as 1,3-dicationic equivalents and undergo a [3 + 3] heteroannulation with 2-naphthols (and meta-substituted phenols) to produce novel polycyclic chromenes possessing spiro-, tri-, and tetrasubstituted carbon centers. The versatility of the method is demonstrated in the synthesis of several chromene-based bioactive natural products. Further, interesting photochromic properties of the new classes of benzo[f]chromenes are also discovered.
Ligand-controlled regiodivergent π-allyl palladium catalysis enables a switch between [3+2] and [3+3] cycloadditions
Xia, Yu,Bao, Qiao-Fei,Li, Yuke,Wang, Li-Jing,Zhang, Bo-Sheng,Liu, Hong-Chao,Liang, Yong-Min
supporting information, p. 4675 - 4678 (2019/05/02)
Reported herein is the use of ligands to tune the regioselectivity and reactivity of palladium-catalyzed [3+2] and [3+3] cycloadditions. Diverse synthesis with vinylethylene carbonates (VECs) as well as free naphthols has been explored to construct four different valuable polycyclic frameworks in a broad substrate scope.
Boronic acid/Br?nsted acid co-catalyst systems for the synthesis of 2: H -chromenes from phenols and α,β-unsaturated carbonyls
Dimakos, Victoria,Singh, Tishaan,Taylor, Mark S.
, p. 6703 - 6711 (2016/07/21)
Protocols for the synthesis of substituted 2H-chromenes from α,β-unsaturated carbonyls and phenols are described. Optimal combinations of arylboronic acids and Br?nsted acids have been identified, such that both can be employed in catalytic quantities to accelerate these condensations. The method has been used to synthesize a variety of substituted 2H-chromenes, as well as photochromic naphthopyrans. The use of pentafluorophenylboronic acid and diphenylphosphinic acid enabled an expansion of the electrophile scope to include α,β-unsaturated ketones. Hall's 'phase-switching' of boronic acids has been exploited to achieve the separation of the two co-catalysts from unpurified reaction mixtures by a simple liquid-liquid extraction.
Synthesis of diverse indene derivatives from 1-diazonaphthalen-2(1 H)-ones via thermal cascade reactions
Somai Magar, Krishna Bahadur,Lee, Yong Rok
supporting information, p. 4288 - 4291 (2013/09/24)
A sequential Wolff rearrangement of 1-diazonaphthalen-2(1H)-ones followed by trapping of the ketene intermediate with primary and aromatic amines or alcohols and phenols in the presence of various aldehydes generates 1H-indene-3-carboxamides or 1H-indene-3-carboxylates. This constitutes an unprecedented three-component coupling reaction that allows for the synthesis of functionalized indene derivatives under catalyst-free thermal conditions.
