N—H.pi(arene) Hydrogen Bonding in 4,4'-Thiodiphenol-Piperazine (1/1)

Abstract

In the 1:1 adduct formed between 4,4'-thiodiphenol [S(C6H4OH)2] and piperazine (CaHI0N2), the components are linked into chains by O--H--.N hydrogen bonds, with an O-..N distance of 2.725 (3)A. These chains are themselves cross-linked into sheets by N--H...Tr(arene) hydrogen bonds. CommentPiperazine (C4HI0N2) is a potentially valuable building block in crystal engineering. It contains two hydrogen-bond acceptor sites and the two N--H bonds are potential hydrogen-bond donors. In addition, there is some structural flexibility available due to both the vari-

Chain, Sheet and Framework Structures in the Adducts of Phenylphosphonic Acid with 4,4'-Bipyridyl (1/1), Piperazine (2/1) and 1,4-Diazabicyclo[2.2.2]octane (2/1)

“…Amine cations. The C--N distances in the piperazine cation in (2) are closer to those observed in the salt-forming 1:2 adduct of piperazine with 4,4'sulfonyldiphenol, 1.477 (3),& (Coupar et al, 1996a), than to those in the neutral 1:1 adduct of piperazine with 4,4'-thiodiphenol, 1.460 (3) and 1.462 (3) A (Coupar et al, 1996b); as usual, protonation at nitrogen leads to an increase in the C--N bond lengths.…”

Centrosymmetric molecular strings in the hydrogen-bonded structure of 4,4'-bipyridyl–4,4'-thiodiphenol (3/2)

“…In suprarnolecular compounds, the big-phenol 4,4'-thiodiphenol, S(C6H4OH)2, invariably acts as a double donor of hydrogen bonds, with neither O nor S acting as hydrogen-bond acceptors. Thus, in combination with double acceptors of hydrogen bonds, this bis-phenol is expected to act as a chain-building unit (Coupar et al, 1996bFerguson et al, 1997). Similarly 4,4'bipyridyl, NCsH4-CsH4N, generally acts as a double acceptor of hydrogen bonds (Coupar et al, 1996a;B6nyei et al, 1998;Ferguson, Glidewell, Gregson & Lavender, 1999;Lavender et al, 1999;Wheatley et al, 1999).…”

Piperazine-1,4-diium–2,4-dinitrophenolate–water (1/2/2)

“…In these adducts, the two components are linked together by either OÐHÁ Á ÁN or NÐHÁ Á ÁO intermolecular hydrogen bonds, depending on the acidity of the phenols or organic acids. In the presence of weak acids, such as 4,4 H -thiodiphenol (Coupar et al, 1996b) or 1,1,1-tris(4-hydroxyphenyl)ethane (Ferguson et al, 1997), piperazine acts solely as an acceptor of OÐHÁ Á ÁN hydrogen bonds, linking the two components into molecular chains. In contrast, with strong acids, such as phenol (Loehlin et al, 1994), 4,4 H -sulfonyldiphenol (Coupar et al, 1996a), dihydrogenphosphate (Char® et al, 1998), 3,4-dihydro-3-butenedione (MacLean et al, 1999) or 3,5-dinitrobenzoic acid (Burchell et al, 2001), piperazine, which is a strongly basic amine, forms a dication and acts as an NÐH hydrogen-bond donor.…”

“…The N1ÐC1 and N1ÐC2 bond distances [1.496 (2) and 1.494 (2) A Ê , respectively] of the piperazine dication are elongated compared with those in unprotonated piperazine [1.460 (3) and 1.462 (3) A Ê ; Coupar et al, 1996b]. The CÐN and CÐC bond distances of the piperazine dication are comparable with those reported for other piperazine dication adducts (Iwasaki & Mutai, 1984;Loehlin et al, 1994;Coupar et al, 1996a;MacLean et al, 1999;Burchell et al, 2001).…”