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Showing papers by "Bryan M. Gatehouse published in 1980"


Journal ArticleDOI
TL;DR: X-ray crystal structure analysis shows that endiandric acid, a constituent of the Australian tree Endiandra introrsa, has the novel racemic structure (1), (1RS,3RS,6SR,7SR,10SR,11RS,12RS,13RS)-(6-phenyltetracyclo[5.4.03,13010,12]trideca-4,8-dien-11-yl]acetic acid) as mentioned in this paper.
Abstract: X-Ray crystal structure analysis shows that endiandric acid, a constituent of the Australian tree Endiandra introrsa, has the novel racemic structure (1), (1RS,3RS,6SR,7SR,10SR,11RS,12RS,13RS)-(6-phenyltetracyclo[5.4.2.03,13010,12]trideca-4,8-dien-11-yl]acetic acid.

51 citations


Journal ArticleDOI
TL;DR: In this article, the title complex [Hg(CH3)(C12HllN)]N03,C13HI4HgN+N03-, 』n03, 』N03- 』
Abstract: The title complex, [Hg(CH3)(C12HllN)]N03,C13HI4HgN+.N03-, has a linear C-Hg-N group with Hg-C 2·07(3) and Hg-N 2·10(2) A; there is a weak intramolecular pi interaction between Hg and a C=C bond of the phenyl ring with Hg-C distances of 3·23(2) and 3·33(3) A.

16 citations



Journal ArticleDOI
TL;DR: In this article, a near linear dominant C-Hg-N unit with additional weak Hg−N bonding was proposed for methylmercury(II) complexes with co-ordination geometries.
Abstract: Methylmercury(II) forms complexes [MeHgL]NO3(L = 2,2′:6′,2″-terpyridyls and di-2-pyridylmethane) where the ligands L are bidentate in methanol, but tridentate and bidentate, respectively, in the solid state with co-ordination geometries for mercury based on a near linear dominant C–Hg–N unit with additional weak Hg–N bonding.

8 citations


Journal ArticleDOI
TL;DR: In this paper, the same authors showed that Methylmercury(II) nitrate reacts with 9-methylguanine (9-MeGua) in water to form solid complexes of stoicheiometry.
Abstract: Methylmercury(II) nitrate reacts with 9-methylguanine (9-MeGua) in water to form solid complexes of stoicheiometry [HgMe(9-MeGuaH–1)], [HgMe(9-MeGua)][NO3], [HgMe(9-MeGua)][NO3]·H2O, and [(HgMe)2(9-MeGuaH–1)][NO3]. Comparison of i.r. spectra of the solid complexes and 1H n.m.r. spectra of [2H6]dimethyl sulphoxide-soluble (ionic) complexes with spectra of analogous guanosine (Guo) complexes indicates that complexes of 9-MeGua and Guo with similar stoicheiometry have the same mode of binding of HgIIMe to the purine ring. The spectra indicate that [HgMe(9-MeGuaH–1)] and [(HgMe)2(9-MeGuaH–1)][NO3] have HgIIMe bonded to N(1) and both N(1) and N(7), respectively, and the complexes [HgMe(9-MeGua)][NO3] and [HgMe(9-MeGua)][NO3]·H2O have HgIIMe bonded to N(7) with retention of a proton at N(1). Crystals of [HgMe(9-MeGua)][NO3] are monoclinic, with a= 4.196(1), b= 15.060(4), c= 18.288(5)A, β= 90.17(2)°, Z= 4, and space group P21/c. The structure has been solved by conventional Patterson and Fourier methods and refined by least-squares techniques to R 0.061 for 1 152 reflections collected by diffractometer. The complex has HgIIMe bound to N(7) with Hg–C 2.06(2), Hg–N(7) 2.09(2)A, and C–Hg–N(7) 175(1)°. Mercury interacts weakly with nearby nitrate ions, with Hg ⋯ 0 2.75(2) and 2.99(2)A; the purine ring is planar with the HgIIMe group slightly tilted from this plane, Hg being –0.168(1) and the carbon atom –0.411(25)A from the plane.

7 citations


Journal ArticleDOI
TL;DR: In this paper, the α-stereochemistry of progesterone derivatives has been established by a full X-ray structural analysis of the α-(4-6η)Pd(acac) derivative of Progestone (Hacac = pentane-2,4-dione).
Abstract: [6β-2H]- and [6α-2H]-Cholest-4-en-3-one react with palladium(II) chloride in dry tetrahydrofuran to give the α-(4–6η)-PdCl compound with highly stereoselective loss of the 6β-deuteron or proton; the α-stereochemistry-has been firmly established by a full X-ray structural analysis of the α-(4–6η)Pd(acac) derivative of progesterone (Hacac = pentane-2,4-dione).

5 citations


Journal ArticleDOI
TL;DR: In this paper, the free energy of activation at 268 K was estimated to be 56'±'8'kJ for the E-3-amino-2-benzoyl-2butenoate.
Abstract: Ethyl-3-amino-2-benzoyl-2-butenoate crystallizes from pentane as either the E (mp 82–84 °C) or the Z-isomer (mp 95.5–96.5 °C). The E isomer is less stable, and changes spontaneously into the Z, which bas been identified by X-ray crystallography. The structure is characterised by an N–H/ester CO hydrogen bond and a very long C2—C3 bond (1.39 A). Nuclear magnetic resonance methods have been used to measure the rate of isomerization at several temperatures, leading to the estimate that the free energy of activation at 268 K is 56 ± 8 kJ.

2 citations




01 Jan 1980
TL;DR: In this article, the structure was refined for 1082 counter-measured observed reflections to R = 0.062, and the complex has a linear C ( 1 ) H g N (1 ) group with Hg-C(1) 2.07 (3) and HgN(1)-N 2.10(2) A; there is a weak intramolecular rc interaction between Hg and a C=C bond of the phenyl ring with H g C distances of 3.23 (2) and 3.33 (3),
Abstract: [Hg(CHs) (CI2HI lN) ]NOs ,CI3HI4HgN+.NO3, is monoclinic, a = 14.887 (4), b = 11. 159 (3), c = 8.745 (3) A, fl = 90.60(3) ° , Z = 4, space group P2~/n. The structure was refined for 1082 counter-measured observed reflections to R = 0.062. The complex has a linear C ( 1 ) H g N ( 1 ) group with Hg-C(1) 2.07 (3) and Hg-N(1) 2.10(2) A; there is a weak intramolecular rc interaction between Hg and a C=C bond of the phenyl ring with H g C distances of 3.23 (2) and 3.33 (3) A.