82632-41-5Relevant academic research and scientific papers
Rhodium-catalyzed intramolecular hydroacylation of 1,2-disubstituted alkenes for the synthesis of 2-substituted indanones
Yuan, Jing,Liu, Chong,Chen, Yan,Zhang, Zhenfeng,Yan, Deyue,Zhang, Wanbin
, p. 269 - 277 (2018/12/05)
The intramolecular hydroacylation of 1,2-disubstituted alkenes was considered to be a challenging task due to the side reactions resulted from the lack of additional substituent at 1-position and the low activity caused by the steric hindrance of substituent at 2-position, and an asymmetric version has not been considered possible due to problems associated with the racemization of the products. We have partially solved these problems. Catalyzed by an activated diphosphine-Rh complex and reacted in a selected dihalogenated solvent, the intramolecular hydroacylation of o-(2-arylvinyl)benzaldehydes provided the corresponding 2-aryl-1-indanones in high yields, and its asymmetric variant using o-(2-alkylvinyl)benzaldehydes afforded chiral 2-alkyl-1-indanones in high yields and with moderate enantioselectivities.
Selective Divergent Synthesis of Indanols, Indanones, and Indenes via Acid-Mediated Cyclization of (Z)- and (E)-(2-Stilbenyl)methanols and Its Application for the Synthesis of Paucifloral F Derivatives
Jongcharoenkamol, Jira,Chuathong, Patsapon,Amako, Yuka,Kono, Masato,Poonswat, Kasam,Ruchirawat, Somsak,Ploypradith, Poonsakdi
, p. 13184 - 13210 (2018/11/02)
Starting from bromo/iodobenzaldehyde derivatives, the corresponding (Z)- and (E)-(2-stilbenyl)methanols could be prepared in 2-5 steps via Pd-catalyzed cross-coupling reactions (Sonogashira and Heck reactions) followed by aryllithium/aryl Grignard addition. For the (E)-stilbenes, subsequent acid-mediated cyclization using p-TsOH immobilized on silica (PTS-Si) at low temperatures furnished the 2,3-trans-1-indanols with complete stereocontrol at the C2-C3. Further oxidization of the alcohol provided the indanones, which are structurally related to the natural product paucifloral F. At higher temperatures, 1,2- and 2,3-disubstituted indenes could be selectively prepared in good to excellent yields. On the other hand, the (Z)-stilbenes, under similar conditions (PTS-Si), did not give the indanols; only the 1,2-disubstituted indenes could be obtained. To gain further insights into the stereochemistry at C2-C3 for the (Z)-stilbenes, hydride or azide was employed as a nucleophile; the corresponding indane products were obtained with the cis stereochemistry at the C2-C3. Thus, the (Z)- or (E)-olefin geometry of the substrate directed the stereoselective indanyl cyclization to furnish the cis or trans at the C2-C3 ring junction, respectively, while reaction conditions controlled the selectivity of the product types.
AuI-catalyzed intramolecular cyclization of 2-alkenylphenyl carbonyl compounds: Exploring the oxophilic Lewis acidity of AuI species
Jagdale, Arun R.,Youn, So Won
supporting information; experimental part, p. 3904 - 3910 (2011/09/15)
A AuI-catalyzed intramolecular cyclization reaction of 2-alkenylphenyl carbonyl compounds to afford a variety of indene, indenol, and indanone ring systems was developed. In this process, AuI serves to activate the carbonyl group of β-keto esters, aldehydes, and ketones, preferentially exhibiting oxophilicity in the presence of C-C multiple bonds. Furthermore, β-keto esters could participate as the electrophilic partner in reactions with carbon nucleophile such as alkenes. Copyright
Cyclopalladiated Aromatic Imines in Organic Synthesis: The Preparation of Cinnamonitriles, Cinnamates, Unsymmetrical Stilbenes, Isoquinolones, and Isoquinolines
Girling, Ian R.,Widdowson, David A.
, p. 1317 - 1324 (2007/10/02)
The preparation and characterisation of some new ortho-palladiated benzaldimine complexes and their reaction with olefins are described.The reaction of di-μ-1-chloro-bis(2-alkyl-2,1-benzazapalladole) complexes (1) with styrene in trifluoroacetic acid-acetic acid mixtures yielded stilbene-2-carbaldehydes (10).These were converted into 2-methyl-3-phenyl-1(2H)-isoquinolones (12) via a mercury(II) mediated cyclisation of the N-methylimine derivatives of the stylbenes.Reaction of the complexes (1) with methyl acrylate produced methyl 2-(N-t-butyliminomethyl)cinnamates (7; Y=CO2Me) and with acrylonitril, the 2-(N-t-butyliminomethyl)cinnamonitriles (7; Y=CN), which upon in situ thermolysis gave the corresponding isoquinolines (8).
CYCLOPALLADATED IMINES IN SYNTHESIS: THE PREPARATION OF UNSYMMETRICAL STILBENES AND 3-ARYLISOQUINOLONES
Girling, I. R.,Widdowson, D. A.
, p. 1957 - 1960 (2007/10/02)
A series of cyclopalladated t-butylimines of aromatic aldehydes were reacted with styrene to give o-formylstilbenes in high yield.The N-methylimines of these were converted to 3-aryl-N-methyl-isoquinolones by oxidation with mercuric acetate.
