6639-05-0Relevant articles and documents
Revision of the structure and stereochemistry of the 2-naphthol-acetaldehyde 2:2 condensation product. A study by X-ray crystallography and the AM1 method
Rashidi-Ranjbar, Parviz,Mohajeri, Ali,Mahmoudkhani, Amir Hossein
, p. 210 - 216 (2001)
The structure of the 2:2 condensation product of 2-naphthol and acetaldehyde, 1-(1-methyl-2,3-dihydro-1H-benzo[f]chromen-3-yl)-2-naphthol, revised by X-ray crystallography, is presented. A moderate intramolecular hydrogen bond is found between the phenolic OH and chromene oxygen atom both in the solid state and in solution. In the crystal structure, the naphthyl groups are oriented in parallel with a π-π stacking distance of 354 pm. AM1 studies are used to explain the formation of one of the four possible stereoisomers for the title compound. Comparison of the experimental and calculated coupling constants indicates that the molecule adopts exclusively the solid-state structure in solution. Copyright
Dibenzoxanthene Derivatives and Related Products from β-Naphthol and Aldehydes or Acetals
Van Allan, James A.,Giannini, Donald D.,Whitesides, Thomas H.
, p. 820 - 823 (1982)
We have investigated several reactions of β-naphthol with aldehydes or aldehyde equivalents.Many of these reactions give novel structures.For example, reaction with paraldehyde does not yield the dinaphthyl acetal as previously reported but instead a compound which we show by spectroscopic methods to be 2-methyl-4-(2-hydroxy-1-naphthyl)benzochroman.Further, reaction with methyl dimethoxyacetate gives a furanone derivative and with malondialdehyde yields a dinaphthodioxabicyclo derivative.The unusual reactions limit the utility of this reaction sequence for the preparation of xanthene derivatives.
Diethyldisulfoammonium chlorometallates as heterogeneous Br?nsted–Lewis acidic catalysts for one-pot synthesis of 14-aryl-7-(N-phenyl)-14H-dibenzo[a,j]acridines
Dutta, Arup Kumar,Gogoi, Pinky,Borah, Ruli
, (2018)
A new series of Br?nsted–Lewis acidic diethyldisulfoammonium chlorometallates, [DEDSA][FeCl4] and [DEDSA]2[Zn2Cl6], were synthesized as solid materials from the reaction of [(Et)2N(SO3H)su
Secondary amine based ionic liquid: An efficient catalyst for solvent free one pot synthesis of xanthenes and benzoxanthenes
Das, Pranab J.,Das, Jupitara
, p. 11745 - 11752 (2015/02/19)
Ionic liquids (IL) prepared from dialkylamines and concentrated sulphuric acid were used in an operationally simple, cost effective, efficient and environmentally benign synthesis of xanthenes and benzoxanthenes. Three ILs were screened for their efficien
Catalytic application of two novel sandwich-type polyoxometalates in synthesis of 14-substituted-14H-dibenzo[a, j]xanthenes
Sheshmani, Shabnam
, p. 345 - 351 (2013/07/26)
Two sandwich-type polyoxometalates K12[As2W 18Cu3O68]·30H2O and K 12[As2W18U3O74] ·21H2O were found to be as novel efficien
Efficient one-pot synthesis of 14-substituted-14H-dibenzo[a,j]xanthenes using boric acid under solvent-free conditions
Karimi-Jaberi, Zahed,Keshavarzi, Mohsen
experimental part, p. 547 - 549 (2011/01/13)
Boric acid efficiently catalysed the one-pot reaction of alkyl or aryl aldehydes with 2-naphthol to afford the corresponding 14-alkyl- or aryl-14H-dibenzo[a,j]xanthenes in good yields under solvent-free conditions.
A new LiBr-catalyzed, facile and efficient method for the synthesis of 14-alkyl or aryl-14H-dibenzo[a,j]xanthenes and tetrahydrobenzo[b]pyrans under solvent-free conventional and microwave heating
Saini, Anil,Kumar, Sanjay,Sandhu, Jagir S.
, p. 1928 - 1932 (2008/02/08)
An efficient method for the synthesis of 14-alkyl or aryl-14H-dibenzo[a,j] xanthenes and tetrahydrobenzo[b]pyrans under solvent-free conventional and microwave heating using lithium bromide, is described. Georg Thieme Verlag Stuttgart.
A new synthesis of dibenzoxanthene derivatives
Kasturi, T. R.,Kumar, K. Ajay
, p. 6 - 11 (2007/10/02)
Oxidation of μ-H/alkylbisnaphthols (4a-g) gives the 14-substituted dibenzoxanthenes (5a-g) as the sole product while that of μ-arylbisnaphthols (4h-j) gives the xanthenes (5h-j) along with the corresponding spironaphthalenones (1h-j).A probable mechan
Synthesis of 14-Alkyl-14H-Dibenzoxanthenes
Sirkecioglu, Okan,Talinli, Naciye,Akar, Ahmet
, p. 502 (2007/10/03)
The synthesis of 14-alkyl-14H-dibenzoxanthenes from aliphatic aldehydes is described.
163. Reactions of Alkenediazonium Salts. Part 1. 2,2-Diethoxyethenediazonium Hexachloroantimonate: A Diazonium, a Carbenium or an Oxonium Salt?
Szele, Ivanka,Tencer, Michal,Zollinger, Heinrich
, p. 1691 - 1703 (2007/10/02)
Reactions of the title compound 1 with various nucleophiles have been studied.The salt behaves like an alkylating agent towards ethers, alcohols and water forming ethyl diazoacetate (2), which reacts further with excess of the nucleophile.A solvent cage mechanism accounting for the observed products is proposed.Thermal decomposition in inert solvents leads to the alkylation of the counter-ion, i.e. formation of chloroethane, and in anisole, alkylation and chlorination of the solvent are also observed.With a standard coupling component, 2-naphtholate ion, no azo coupling reaction of 1 is observed, but instead 14-methyl-14H-dibenzoxanthene (17) is formed.The products of the reaction with diethylamine are diethylcyanoformamide (18) and ethyl diethylcarbamate (19).None of the chemistry of salt 1 is explained by the intervention of vinyl cations expected to be formed in a heterolytic dediazoniation.The predominant pathways seems to involve reactions of an oxonium salt (alkylating properties) or, in the case of diethylamine, a carbenium salt (primary nucleophilic attack on the β-C-atom of 1).The free energy barrier to C=C rotation in 1 is estimated to be 75 to 77 kJ/mol (18.0 to 18.5 kcal/mol), a value which falls between those expected for a double and a single bond.
