Melemium Hydrogensulfate H₃C₆N₇(NH₂)₃(HSO₄)₃ – the First Triple Protonation of Melem

Abstract

Wehave synthesized melemium hydrogensulfate H 3 C 6 N 7 (NH 2 ) 3 (HSO 4 ) 3 by reaction of melem with 70 % sulfuric acid. The crystal structure was elucidated by single-crystal XRD (P2 1 /n (no. 14), Z = 4, a = 10.277(2), b = 14.921(3), c = 11.771(2) Å, β = 99.24(3)°, V = 1781.5(6) Å 3 ). H 3 C 6 N 7 (NH 2 ) 3 (HSO 4 ) 3 is the first compound displaying a triple protonation of melem.In this contribution an overview of accessible melemium sulfates depending on the concentration of sulfuric acid is given. Two additional melemium sulfates were identified this way.

A Tour‐Guide through Carbon Nitride‐Land: Structure‐ and Dimensionality‐Dependent Properties for Photo(Electro)Chemical Energy Conversion and Storage

“…In melamine salts [54] and in tricyanomelaminates, [8c,55] protonation occurs on the triazine ring rather than the peripheral group, NH 2 or NCN, as illustrated in the pyrophosphate salt of melamine in Figure 4a. Similarly for salts of melem, [56] and as implied in the cyamelurate tautomerism [41] discussed above, protonation also occurs on the heptazine ring rather than the groups on the 2-, 5-, 8-position; an example is shown in Figure 4b for the hydrogen sulfate salt of melem. In spite of these examples illustrating their basicity, the pKa of melamine and related compounds such as ammeline and ammelide have been measured to be ≤5, that is, on a similar order of magnitude as organic acids.…”

Synthesis and Structure of Melamium Bromide C6N11H10Br and Melamium Iodide C6N11H10I

“…monoprotonated melam) have been even less investigated. While there are plenty of reports on melemium salts there is extremely little work on salts containing the melamium ion. A rather simple route has been proposed for synthesis of melamium salts of inorganic acids starting from melam and either a solution of the respective acid, or its ammonium salt as a compound able to liberate the acid.…”

Template‐Free Synthesis of Three‐Dimensional Nanoporous Bulk Graphitic Carbon Nitride with Remarkably Enhanced Photocatalytic Activity and Good Separation Properties

“…The former exhibits a stronger intensity and a higher angle for the diffraction peak compared to that of H-CN, whereas the latter shows a decreased intensity. This phenomenon could reasonably be explained by the following: (1) as the interlayer structure of g-C 3 N 4 is stabilized by van der Waals interactions and hydrogen-bonding interactions, the protonation will lead to enhanced interlayer structural connections by introducing stronger hydrogen-bonding interactions [19] (from 0.324 to 0.322 nm) and (2) the in-plane order is lowered after the protonation. [20] It is worth mentioning that the zeta potential of the B-CN (-16.9 mV) and the www.eurjic.org FULL PAPER Table 1.…”