n-Dodecylammonium Chloride

Abstract

The redetermination of the structure of C12H28N+.C1 -corroborates and complements the limited data of a prior less accurate study. The structure consists of C12H28N ÷ chains arranged head-to-tail in layers between layers of C1-ions. CommentThe structure of dodecylammonium bromide has been reported previously along with a preliminary (projection) determination of dodecylammonium chloride (Gordon, Stenhagen & Vand, 1953). A more recent study of decylammonium chloride (DACI) and dodecylammonium chloride (DDAC1) (Pinto, Vencato, Gallardo & Mascarenhas, 1987) resulted in the latter complex being solved from only 337 observed reflections using isotropic displacement factors. It was suggested (Pinto et al., 1987) that the finding that the reflection intensities were weak for both compounds was perhaps due to the closeness of a phase transition (Gault, Gallardo & Muller, 1985), which may provoke crystalline disorActa Crystallographica Section C ISSN 0108-2701 ©1995 J. SILVER, P. J. MARSH AND C. S. FRAMPTON 2433 der. Unfortunately, the temperature of the data collection was not reported (Pinto et al., 1987). As part of a programme of work on layer structures, we wished to have a more accurate solution of DDAC1, (I), and we report here the results of that study. (I) "I~he present structure was solved using 1299 observed reflections and 239 variables (reflection to parameter ratio 5.44:1, which is just acceptable). The refinement also included H atoms. The structure of (I) is shown in Fig. 1 and a packing diagram is presented in Fig. 2. The structure is essentially the same in layout as previously reported (Pinto et al., 1987). The bond lengths, however, are more accurate. Refinement of the H atoms led to C--H distances in theorange 0.86-1.10,~ and N--H distances of 0.83-1.05 A. The H-atom B values ranged from 2.9 to 9.0 ,~2 with a mean of 5.0 ~2. DAC1 and similar to that found for lauric acid (Vand, Morley & Lomer, 1951). The chain length as measured from N(1) to C(12) is 15.155 (5),~,.The carbon chains form a layer so that the tail of one stops just short of the next CI-layer and the NHJ-heads of the three neighbouring chains overlap this tail balancing the charge in the C1-layer. Thus, the packing of the carbon chains can be considered as two interdigitated layers (Fig. 2). At 318 K, DDAC1 is found to undergo a phase transition to an interlayer spacing of 30A (Gault et al., 1985). This spacing is about double the chain length and could be explained by the two interdigitated layers in the low-temperature phase moving apart in the high-temperature phase allowing the chains the freedom to rotate. ExperimentalThe title compound was prepared from n-dodecylamine and HCI. Crystals were grown from an ethanol solution.('~ (~ The displacement ellipsoids are drawn at 50% probability levels and H atoms are drawn as small circles of arbitrary radii. Crystalline cohesion is achieved by ionic bonds between the --NH~ cations and the C1-anions, and van der Waals interactions between the carbon chains. There are three close CI(1...

n-Undecylammonium Chloride Monohydrate

“…The C--C distances vary between 1.514(2) and 1.526 (2) ,~,, the C--N distance is 1.494 (2) ,~ and the C--C----C(N) angles are in the range 111.3 (1)-113.9 (1) °. Unlike previous findings for DAC1 and DDAC1 (Pinto, Vencato, Gallardo & Mascarenhas, 1987;Silver, Marsh & Frampton, 1995), there is no evidence of stress in the bond lengths and angles, although the torsion angles and Fig. 2 show that the UDA chains are distorted from a fully extended conformation on packing.…”

“…The UDA chains are intercalated ( Fig. 2) and held together by van der Waals forces in a manner similar to that found in both DAC1 and DDAC1 (Pinto, Vencato, Gallardo & Mascarenhas, 1987;Silver, Marsh & Frampton, 1995), except that the water molecule causes displacement of the methyl terminal of the nearest UDA chain so that intercalation is less than that found in the former anhydrous structures.…”

“…There are also two close C1.. -O contacts of 3.180 (1) and 3.226 (1) A, which suggests further possible hydrogen-bonding interactions. These N...C1 hydrogen-bond lengths are between 0.03 and 0.18 ,~ longer than those found in both DAC1 (Schenk & Chapuis, 1986) and DDAC1 (Silver, Marsh & Frampton, 1995), as would be expected where a more extensive hydrogen-bonding network occurs (caused by the incorporation of water molecules into the structure). It is worth noting that the N...CI distances in UDAC1H20 are shorter than those found for the CI-to-DDA chains in (C12H25NH3)2[MnC14] layer structures, which are 3.27, 3.28 and 3.38 A (Ciajolo, Corradini & Pavone, 1976).…”

“…The structures of ndecylammonium chloride (DACI; Schenk & Chapuis, 1986;Pinto, Vencato, Gallardo & Mascarenhas, 1987) and n-dodecylammonium chloride (DDAC1; Pinto, Vencato, Gallardo & Mascarenhas, 1987;Silver, Marsh & Frampton, 1995) have been described and used to interpret solid-solid phase transitions (Gault, Gallardo & Muller, 1985;Kind et al, 1982;Seliger, Zagra, Blinc, Arend & Chapuis, 1983;Silver, Marsh & Frampton, 1995). The title compound, n-undecylammonium chloride monohydrate, UDAC1H20, represents the first of what appears to be a new class of these compounds containing a hydrogen-bonded water molecule.…”

Crystal structures and phase transitions of long-chain n-alkylammonium bromide monohydrates

“…The single crystal structures of three anhydrous, long-chain n-alkylammonium halides have been reported in the literature, namely n-decylammonium chloride, 10 n-dodecylammonium chloride 11 and n-dodecylammonium bromide.…”