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Ian McClenaghan

Publications and source records attributed to Ian McClenaghan.

8 recordsLinked to original sources
PubMed2004

2-Acetamido-4-p-tolyl-1,3-thiazole and 2-amino-4-p-tolyl-1,3-thiazolium chloride dihydrate.

The structures of 2-acetamido-4-tolyl-1,3-thiazole, C(12)H(12)N(2)OS, (I), and 2-amino-4-tolyl-1,3-thiazolium chloride dihydrate, C(10)H(11)N(2)S(+).Cl(-).2H(2)O, (II), reveal that both molecules are essentially planar, with the respective dihedral angles between the benzene and thiazole rings being 2.9 (1) and 10.39 (7) degrees . Compound (I) associates via a single N-H...O interaction to form a flat alternate-facing hydrogen-bonded chain [graph-set C(2)(2)(4)]. Compound (II) packs with the hydrogen-bonding associations of the Cl atoms and the water molecules creating a convoluted hydrogen-bonded ribbon made up of five-membered donor-acceptor rings, involving three water O atoms (with associated H atoms) and two Cl atoms. The thiazolium rings form stacked columns, aligned in the same direction as the hydrogen-bonded ribbons, of alternate-facing molecules that are also involved in the hydrogen-bonding network, linking to the Cl atoms and one of the water molecules. Subsequently, each Cl atom is the hydrogen-bond acceptor for five separate O/N-H associations.

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PubMed2003

Four trifluoromethylnitrobenzene analogues.

The crystal structures of four trifluoromethylnitrobenzene analogues (CF(3))C(6)H(3)(NO(2))[C(4)H(8)N(2)]R (where C(4)H(8)N(2) is piperazinyl and R is ethyl carboxylate, CO(2)C(2)H(5), or phenyl, C(6)H(5)), have been determined, and their conformations and packing arrangements are compared. The four compounds are ethyl 4-[4-nitro-2-(trifluoromethyl)phenyl]piperazine-1-carboxylate, (I), and ethyl 4-[2-nitro-4-(trifluoromethyl)phenyl]piperazine-1-carboxylate, (II), both C(14)H(16)F(3)N(3)O(4), and 1-[4-nitro-2-(trifluoromethyl)phenyl]-4-phenylpiperazine, (III), and 1-[2-nitro-4-(trifluoromethyl)phenyl]-4-phenylpiperazine, (IV), both C(17)H(16)F(3)N(3)O(2). All molecules adopt a rod-like conformation, while the asymmetric units of (II) and (IV) contain two unique molecules that pack as monodirectional pairs. All molecules pack with C-H...O/F close contacts to all but one of the O atoms and to five of the 18 F atoms.

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PubMed2003

2-Phenylmalonpiperadide and 2-phenylmalonmorpholide.

The structures of 2-phenylmalonpiperadide [systematic name: 2-phenyl-1,3-bis(piperidin-1-yl)propane-1,3-dione, C(19)H(26)N(2)O(2), (I)] and 2-phenylmalonmorpholide [systematic name: 1,3-dimorpholino-2-phenylpropane-1,3-dione, C(17)H(22)N(2)O(4), (II)], have been determined and both their molecular conformations and packing arrangements compared. Although chemically similar, compounds (I) and (II) exhibit different molecular conformations. The only general conformational similarities are that their respective carbonyl groups are orientated in the same direction and the heterocyclic rings exist in the chair arrangement. General similarities in the packing arrangements arise due to both compounds having the same space group (P2(1)2(1)2(1)) and a similar alignment of their phenyl-substituted backbone with respect to the c axis. Similar C-H.O hydrogen-bonding associations are listed for the carbonyl O atoms, while only one of the morpholine O atoms is involved in any such association.

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PubMed2003

1-(4-chlorophenylsulfanyl)-2-nitro-4-(trifluoromethyl)benzene and 1-(4-chlorophenylsulfanyl)-4-nitro-2-(trifluoromethyl)benzene.

Two chemical isomers of 3-nitrobenzotrifluoride, namely 1-(4-chlorophenylsulfanyl)-2-nitro-4-(trifluoromethyl)benzene, C(13)H(7)ClF(3)NO(2)S, (I), and 1-(4-chlorophenylsulfanyl)-4-nitro-2-(trifluoromethyl)benzene, C(13)H(7)ClF(3)NO(2)S, (II), have been prepared and their crystal structures determined with the specific purpose of forming a cocrystal of the two. The two compounds display a similar conformation, with dihedral angles between the benzene rings of 83.1 (1) and 76.2 (1) degrees, respectively, but (I) packs in P-1 while (II) packs in P2(1)/c, with C-H.O interactions. No cocrystal could be formed, and it is suggested that the C-H.O associations in (II) prevent intermolecular mixing and promote phase separation.

Journal Article↗
PubMed2002

Three 2-aminopurine derivatives.

The structure of 2-amino-6-chloropurine, C(5)H(4)ClN(5), (I), comprises a flat molecule, with all possible strong hydrogen-bond donors and acceptors involved in the hydrogen-bonding network. The structures of 2-amino-6-(4-chlorophenylsulfanyl)purine hemihydrate, C(11)H(8)ClN(5)S.0.5H(2)O, (II), and 2-amino-6-(4-methylphenylsulfanyl)purine 0.33-hydrate, C(12)H(11)N(5)S.0.33H(2)O, (III), have two and three unique molecules, respectively, and one water molecule in their asymmetric units. Both (II) and (III) exhibit elaborate hydrogen-bonding networks that involve the S (for both) and Cl [for (II)] atoms in addition to the expected strong hydrogen-bonding sites. Both structures also have offset-stacking formations of the phenyl and purine rings.

2-Aminopurine↗
PubMed2002

2-(Pyrrolidin-1-yl)-1,4-naphthoquinone and 2-phenylsulfanyl-3-(pyrrolidin-1-yl)-1,4-naphthoquinone.

The structure of 2-(pyrrolidin-1-yl)-1,4-naphthoquinone, C(14)H(12.95)Cl(0.05)NO(2), (I), is actually a 0.95:0.05 mixture including 2-chloro-3-(pyrrolidin-1-yl)-1,4-naphthoquinone as a minor impurity, but (I) was resolved as a single molecule containing a Cl atom with 5% occupancy at the 3-position. Compound (I) was prepared from the fully chloro-substituted analogue in an attempt to produce the disubstituted pyrrolidinyl derivative. 2-Phenylsulfanyl-3-(pyrrolidin-1-yl)-1,4-naphthoquinone, C(20)H(17)NO(2)S, (II), was also prepared from 2-chloro-3-(pyrrolidin-1-yl)-1,4-naphthoquinone, using a strong exocyclic nucleophile. The structure of (II) differs from previous structures of 2,3-dichloro-1,4-naphthoquinone and its derivatives in that the naphthoquinone ring is non-planar.

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PubMed2002

1-(2-Pyridyl) ethan-1-one 8-quinolylhydrazone and 1-(1H-pyrrol-2-yl) ethan-1-one 8-quinolylhydrazone.

The structures of the title compounds, C(16)H(14)N(4), (I), and C(15)H(14)N(4), (II), respectively, have been determined, and their molecular packing arrangements compared. Both are essentially flat molecules, with respective dihedral angles between the quinoline and heterocyclic rings of 19.0 (1) and 8.5 (2) degrees. The pyridyl derivative, (I), packs in a P2(1)/c unit cell, while in the pyrrolyl compound, (II), the molecules pack in Pca2(1) and form a crinkled ribbon arrangement through the association of pyrrole NH groups with the quinoline N atoms.

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