The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《The crystal structure of copper(II) succinate dihydrate》. Authors are O’Connor, B. H.; Maslen, E. N..The article about the compound:Bis(2,2,6,6-tetramethyl-3,5-heptanedionato)nickel(II)cas:14481-08-4,SMILESS:CC(C)(C1=O[Ni+2]2(O=C(C(C)(C)C)[CH-]1)O=C([CH-]C(C(C)(C)C)=O2)C(C)(C)C)C).Name: Bis(2,2,6,6-tetramethyl-3,5-heptanedionato)nickel(II). Through the article, more information about this compound (cas:14481-08-4) is conveyed.
The crystal structure of the title compound has been established by vector methods with 3-dimensional single crystal x-ray data. The at. parameters were refined by the diagonal least sqs. approximation, the final R index being 0.095. The crystal structure has P1̅ space-group symmetry and the coordinates are defined most suitable relative to a cell of dimensions a 6.437 ± 0.011, b 7.623 ± 0.004, c 8.081 ± 0.005 A., α 103° 54′ ± 8′, β 73° 30′ ± 21′, γ 98° 37′ ± 13′. The structure consists of infinite chains of covalently bonded binuclear units each of which closely resembles the Cu(OAc)2.H2O configuration. The Cu-Cu distance of 2.610(1) A. confirms that there is magnetic exchange between the two copper atoms in each binuclear unit.
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Reference:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics