1,5-Diamino-1H-tetrazole (2, DAT) can easily be protonated by reaction with strong mineral acids, yielding the poorly investigated 1,5-diaminotetrazolium nitrate (2a) and perchlorate (2b). A new synthesis for 2 is introduced that avoids lead azide as a hazardous byproduct. The reaction of 1,5-diamino-1H-tetrazole with iodomethane (7a) followed by the metathesis of the iodide (7a) with silver nitrate (7b), silver dinitramide (7c), or silver azide (7d) leads to a new family of heterocyclic-based salts. In all cases, stable salts were obtained and fully characterized by vibrational (IR, Raman) spectroscopy, multinuclear NMR spectroscopy, mass spectrometry, elemental analysis, X-ray structure determination, and initial safety testing (impact and friction sensitivity). Most of the salts exhibit good thermal stabilities, and both the perchlorate (2b) and the dinitramide (7c) have melting points well below 100 degrees C, yet high decomposition onsets, defining them as new (7c), highly energetic ionic liquids. Preliminary sensitivity testing of the crystalline compounds indicates rather low impact sensitivities for all compounds, the highest being that of the perchlorate (2b) and the dinitramide (7c) with a value of 7 J. In contrast, the friction sensitivities of the perchlorate (2b, 60 N) and the dinitramide (7c, 24 N) are relatively high. The enthalpies of combustion (Delta(c)H degrees ) of 7b-d were determined experimentally using oxygen bomb calorimetry: Delta(c)H degrees (7b) = -2456 cal g(-)(1), Delta(c)H degrees (7c) = -2135 cal g(-)(1), and Delta(c)H degrees (7d) = -3594 cal g(-)(1). The standard enthalpies of formation (Delta(f)H degrees ) of 7b-d were obtained on the basis of quantum chemical computations using the G2 (G3) method: Delta(f)H degrees (7b) = 41.7 (41.2) kcal mol(-)(1), Delta(f)H degrees (7c) = 92.1 (91.1) kcal mol(-)(1), and Delta(f)H degrees (7d) = 161.6 (161.5) kcal mol(-)(1). The detonation velocities (D) and detonation pressures (P) of 2b and 7b-d were calculated using the empirical equations of Kamlet and Jacobs: D(2b) = 8383 m s(-)(1), P(2b) = 32.2 GPa; D(7b) = 7682 m s(-)(1), P(7b) = 23.4 GPa; D(7c) = 8827 m s(-)(1), P(7c) = 33.6 GPa; and D(7d) = 7405 m s(-)(1), P(7d) = 20.8 GPa. For all compounds, a structure determination by single-crystal X-ray diffraction was performed. 2a and 2b crystallize in the monoclinic space groups C2/c and P2(1)/n, respectively. The salts of 7 crystallize in the orthorhombic space groups Pna2(1) (7a, 7d) and Fdd2 (7b). The hydrogen-bonded ring motifs are discussed in the formalism of graph-set analysis of hydrogen-bond patterns and compared in the case of 2a, 2b, and 7b.

Outstripping lithium bases: A wide range of polyfunctional aryl and heteroaryl magnesium reagents were efficiently prepared in THF by direct magnesiation with (tmp)2Mg⋅2 LiCl, an exceptionally active base. These compounds can serve as intermediates in natural product synthesis. In the example shown a palladium‐catalyzed cross‐coupling reaction is used to prepare a derivative of salicylic acid.

A range of aryl and heteroaryl organometallics are efficiently prepared in THF via directed ortho metalation by using the previously reported amide bases tmpMgCl·LiCl (tmp = 2,2,6,6-tetramethylpiperidyl), tmp2Mg·2LiCl and tmp2Zn·2MgCl2·2LiCl. These metalation reactions are carried out at 80−100 mmol scale. The unsaturated organometallic compounds undergo smooth reactions with various electrophiles, e.g. additions to carbonyl groups, Pd-catalyzed cross-coupling reactions or Cu-catalyzed acylations. In all cases, the metalation rates have been compared with corresponding small-scale reactions (1−2 mmol). Moreover, a procedure for the recovery of the valuable tmp-H from the aqueous layer is reported.

Getting directions: The (Me2N)2P(O)O substituent serves as an effective directing‐metalation group in the magnesiation of substituted arenes with TMP2Mg⋅2 LiCl (see scheme). This reaction can be used to achieve difficult substitution patterens by meta,para or para,meta functionalization. TMP=2,2,6,6‐tetramethylpiperamidyl, NEP=N‐ethylpyrrolidone.

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