Molecular recognition among alcohols and amines: super-tetrahedral crystal architectures of linear diphenol–diamine complexes and aminophenols

Crystal Engineering Using Tris-phenols. Cross-Linked, Pairwise-Interwoven Two-Dimensional Nets in the 2:1 Adduct of 1,1,1-Tris(4-hydroxyphenyl)ethane with 1,2-Diaminoethane

“…In (1), as well as in [{Mn(CO)3(#3-OH)}n].H2NCH2CH2NH2 (Copp et al, 1992), the diamine acts solely as a bis-acceptor of O-H.. • N hydrogen bonds; in the 2:1 adduct with phenol, (C6HsOH)z.H2NCH2CH2NH2 (Loehlin et al, 1994), and in the methanol-solvated 2:1 adduct with 4,4'-biphenol, (HOC6HaC6HaOH)2.H2NCH2CH2NH2.MeOH (Ferguson, Glidewell, Gregson, Meehan & Patterson, 1998), each nitrogen is both an acceptor and a single donor, while in the 1:1 adduct with 4,4'-biphenol each N atom of the diamine acts as a single donor and double acceptor of hydrogen bonds in a continuous threedimensional diamondoid network (Ferguson, Glidewell, Gregson, Meehan & Patterson, 1998). Only in the 1:1 adduct with 4,4'-biphenol is the idealized complementarity (Ermer & Eling, 1994) of NH2 groups (as double donors and single acceptors of hydrogen bonds) and OH groups (as single donors and double acceptors) apparent. In all these adducts the diamine adopts a trans conformation, which is nearly, or precisely, planar.…”

“…1 (4) in addition, four of the O atoms (Oll, O13, O21 and 022) also act as acceptors in O--H...O hydrogen bonds. The complementarity of hydrogen-bond donor and acceptor capacities between amino groups and hydroxyl groups, postulated as a mechanism for molecular recognition among alcohols and amines (Ermer & Eling, 1994), is clearly not manifest in (1); indeed, it is noteworthy that while two of the O atoms (O12 and 023) do not act as acceptors in O-H...O hydrogen bonds, neither do they so act in N--H...O hydrogen bonds, despite the plenitude of free N--H bonds in the structure. Indeed, even the shortest (N)-TH...O distance in the structure is, at 2.666(3) A, only marginally less than the corresponding sum of van der Waals radii, 2.72 A.…”

Crystal Engineering: Strategies and Architectures

“…A monumental article by Ermer & Eling (1994) describes the hydrogen-bond complementarity of hydroxy (two acceptors-one donor) and amino (one acceptortwo donors) groups, and proceeds to illustrate how alcohols and primary amines can be combined in 1:1 cocrystals whilst forming predictable structural motifs, Fig. 3.…”

Supramolecular Alcohol–Amine Crystals and Their Hydrogen-Bond Patterns

“…When this occurs, these structures will have three hydrogen bonds around each O atom (and around each nitrogen). Ermer & Eling (1994) recognized this class of complementary compounds and introduced the concept of`saturated hydrogen bonding' (SHB). They examined a series of cocrystals between symmetric aromatic diamines and diols.…”

“…Probably the ®rst published structure with this feature is that of p-aminophenol (AMPHOL) by Brown (1951), although he was unable to determine the H-atom positions. Ermer & Eling (1994) carried out a redetermination of Brown's structure and located the H atoms. The credit for the ®rst detailed structure of this type should be given to Liminga (1967) who gave a thorough analysis of hydrazine±bis(ethanol) (HYDETH).…”