126-81-8Relevant articles and documents
Cyclocondensation of 2-aminobenzimidazole with dimedone and its arylidene derivatives
Lipson,Desenko,Shishkina,Shirobokova,Shishkin,Orlov
, p. 1041 - 1047 (2003)
The reactions of 2-aminobenzimidazole with substituted benzaldehydes and dimedone, 2-arylidene derivatives of dimedone, 9-arylhexahydro-1H-xanthene-1,8(2H)-diones and also with dimedone and DMF have been studied. The direction of formation of the pyrimidine ring has been established and discussed. An X-ray structural investigation of 2,2-dimethyl-2,3-dihydrobenzimidazo[1,2-a]quinazolin-4(1H)-one has has been carried out.
Two phases of C9H12O4: Why is the structure at 295 K so complicated?
Duncan, Laura L.,Patrick, Brian O.,Brock, Carolyn Pratt
, p. 502 - 511 (2002)
Molecules of 4,4′-dimethyl-2-hydroxy-6-oxocyclohexene-1-carboxylic acid, C9H12O4, crystallize at 295 K in a modulated superstructure with five half-molecules in the asymmetric unit; each molecule is located on one of the mirror planes of the space group Cmc21. Reflections with k ≠ 5n are systematically weak; a satisfactory refinement can be obtained in a Cmcm pseudocell having b′ = b/5. The important modulation involves small rotations of the molecules around axes perpendicular to the mirror plane; there is also an up/down disorder of the CMe2 fragment in four of the five molecules (two molecules with occupancy factors ca 4:1; two with occupancy factors ca 3:2). The modulation is a response to packing problems that can be traced to the differences between the thin, electron-and oxygen-rich 'head' of the molecule and the thicker, methyl-rich 'tail'. At 130 K the length of b is reduced by 2/5 and the Pmnb structure is ordered. Both structures can be described as modulated variants of the Cmcm substructure; the wavevectors are 2b′*/5 for the room-temperature structure and b′*/2 for the low-temperature structure, where b′* is the reciprocal axis of the subcell. The structure at room temperature can also be understood as a hybrid of the fully disordered pseudocell structure and the ordered structure that is found at low temperature.
Zinc chloride catalyzed collective synthesis of arylmethylene bis(3-hydroxy-2-cyclohexene-1-ones) and 1,8-dioxo-octahydroxanthene/acridine derivatives
Ganesan, Subramaniapillai Selva,Kothandapani, Jagatheeswaran,Ganesan, Asaithampi
, p. 682 - 687 (2015/04/14)
Catalytic amount of ZnCl2 efficiently promoted rapid synthesis of arylmethylene bis(3-hydroxy-2-cyclohexene-1-one) in water at room temperature in excellent yield. At elevated temperature, ZnCl2 also catalyzed one-pot synthesis of 1,8-dioxo-octahydroxanthene and 1,8-dioxo-decahydroacridine derivatives in good yield. In specific instances, unusual dissociation of dimedone from the arylmethylene bis(3-hydroxy-2-cyclohexene-1-one) was identified in the reaction medium. It was minimized/avoided by the addition of known excess dimedone to the reaction mixture in the one-pot synthesis of 1,8-dioxo-octahydroxanthene.
Synthesis of enaminones in aqueous media using catalytic dilute HCl
Cui, Bin,Wang, Rui-Hua,Chen, Li-Zhuang,Jin, Yan,Han, Guang-Fan
scheme or table, p. 1064 - 1070 (2011/04/26)
(Chemical Equation Presented) A green and convenient approach to the synthesis of β-enaminones from aromatic amines and 5-substituted-1,3- cyclohexanedione in the presence of dilute hydrochloric acid (30 mmol=L) as a catalyst in solvent-free media is described. This method provides several advantages such as environmental friendliness, low cost, good yields, and simple workup procedure. Copyright Taylor & Francis Group, LLC.
