562847-48-7Relevant articles and documents
Technique for producing insecticide from carbon dioxide
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Paragraph 0047; 0049-0051; 0099-0103; 0139-0143, (2019/03/31)
A technique for producing an insecticide from carbon dioxide comprises the following steps: weighing a 1,3-cyclohexanedione substrate, a catalyst and Cs2CO3 in a Schleck bottle, degassing, and continuously introducing 1 atm carbon dioxide; adding a solven
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 (2007/10/03)
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.