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Louis J. Farrugia

Bio: Louis J. Farrugia is an academic researcher from University of Glasgow. The author has contributed to research in topics: Crystal structure & Charge density. The author has an hindex of 34, co-authored 243 publications receiving 49150 citations. Previous affiliations of Louis J. Farrugia include University of British Columbia & University of Jyväskylä.


Papers
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Journal ArticleDOI
TL;DR: In this paper, the structure of Na2WO4·2H2O has been corrected according to the entries in the Inorganic Crystal Structure Database (ICSD) and the H-atom positions were observed and refined satisfactorily with anisotropic displacement parameters.
Abstract: There have been two previous structure determinations of the title compound, Na2WO4·2H2O: in 1969 [Mitra & Verma (1969). Indian J. Chem. 7, 598–602] and in 1974 [Okada et al. (1974a). Bull. Tokyo Inst. Technol. 120, 7–11]. However, both structures are incorrect according to their entries in the Inorganic Crystal Structure Database [(2007), URL: http://www.fiz-karlsruhe.de/ecid/Internet/en/DB/icsd/index.html]. Despite the high absorption coefficient, the H-atom positions could be observed and refined in the present study. Owing to the accurate analytical absorption correction, all non-H atoms could be refined satisfactorily with anisotropic displacement parameters. There are hydrogen-bonding inter­actions between all H atoms and the O atoms of the tungstate dianion.

10 citations

Journal ArticleDOI
TL;DR: Stereoselective epoxidation and dihydroxylation of the syn-(4aS,10bS)-phenanthridone framework was investigated leading to the preparation of new analogues of 7-deoxypancratistatin.
Abstract: A new synthetic approach has been developed for the preparation of 7-deoxypancratistatin analogues bearing a syn-(4aS,10bS)-phenanthridone ring junction. A one-pot tandem process involving a substrate-directed Overman rearrangement and ring closing metathesis reaction was developed for the stereoselective synthesis of a carbocyclic allylic trichloroacetamide. Conversion to a 6-bromopiperonyl amide, followed by a Heck reaction generated a homoallylic alcohol and completed the syn-(4aS,10bS)-phenanthridone carbon skeleton. Stereoselective epoxidation and dihydroxylation of the syn-(4aS,10bS)-phenanthridone framework was then investigated leading to the preparation of new analogues of 7-deoxypancratistatin.

10 citations

Journal ArticleDOI
TL;DR: A series of Ru(II)-benzene organometallic compounds (1, 6) constructed from [RuCl2(η6-benzenes)]2 and chiral aroylthiourea ligands (L1-L6) obtained from D/L-phenylalanine, was fully characterized as mentioned in this paper.

10 citations

Journal ArticleDOI
TL;DR: In this paper, the structure of the cluster compounds [RuRh3(µ3-CO)2(CO)3(η-C5Me5)3] was established by single-crystal X-ray diffraction studies.
Abstract: The compounds [Ru(η6-C8H10)(cod)](C8H10= cycle-octa-1,3,5-triene, cod = cycle-octa-1,5-diene) and [Rh(CO)2(η-C5Me5)] react in toluene at 60 °C to give the cluster compounds [RuRh3(µ3-CO)2(CO)3(η-C5Me5)3](1) and [RuRh2(µ-CO)(µ3-CO)(CO)2(η4-C8H10)(η-C5Me5)2](2). The structures of these compounds were established by single-crystal X-ray diffraction studies. Compound (1) has a distorted tetrahedral RuRh3 metal atom core [Rh–Rh 2.684(1)–2.739(1), Ru–Rh 2.620(1)–2.715(1)A]. The rhodium atoms are each ligated by an η-C5Me5 group, the ruthenium atom is terminally bonded to three carbonyl groups, while the remaining two CO ligands triply and asymmetrically bridge the Rh3 face and one RuRh2 face of the metal polyhedron. In compound (2) the C8H10 ligand attached to the ruthenium is bicyclo[4.2.0]octa-2,4-diene. The molecule comprises a metal atom triangle [Ru–Rh 2.766(1) and 2.815(1), Rh–Rh 2.672(1)A] and an η-C5Me5 group is co-ordinated to each rhodium atom. The four CO ligands show a remarkable variety of bonding modes. One carbonyl group attached to the ruthenium atom is essentially terminally bound to that centre [Ru–C–O 167.5(4)°], while a second carbonyl group attached to the ruthenium semi-bridges an edge of the metal triangle [Ru–C–O 158.1(4)°; Ru–CO 1.930(4), Rh ⋯ CO 2.412(5)A]. The Rh–Rh vector is symmetrically bridged by another CO ligand [Rh–C–O 137.3(3) and 138.2(3)°, Rh–CO 1.989(3) and 2.000(4)A]. The remaining carbonyl group asymmetrically bridges the face of the triangle [Ru–CO 2.247(4), Rh–CO 2.038(4) and 2.069(4)A]. Spectroscopic studies (i.r. and n.m.r.) on (1) and (2) are reported. Both compounds show site exchange of CO groups in solution (13C-{lH} n.m.r.) but the process in (1) is limited to the Ru(CO)3 group, with the dynamic behaviour persisting at –80 °C. With (2), at room temperature, all four CO ligands exchange, but at –80 °C separate signals for the µ-CO and µ3-CO groups are seen, although only one resonance is observed for the two CO groups attached to the ruthenium atom. These and other data are discussed, and a mechanism proposed to account for the formation of (1) and (2).

10 citations


Cited by
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TL;DR: The category Computer Program Abstracts provides a rapid means of communicating up-to-date information concerning both new programs or systems and signi®cant updates to existing ones.
Abstract: The category Computer Program Abstracts provides a rapid means of communicating up-to-date information concerning both new programs or systems and signi®cant updates to existing ones. Following normal submission, a Computer Program Abstract will be reviewed by one or two members of the IUCr Commission on Crystallographic Computing. It should not exceed 500 words in length and should follow the standard format given on page 189 of the June 1985 issue of the Journal [J. Appl. Cryst. (1985). 18, 189± 190] and on the World Wide Web at http://www.iucr. org/journals/jac/software/. Lists of software presented and/or reviewed in the Journal of Applied Crystallography are available on the World Wide Web at the above address, together with information about the availability of the software where this is known.

18,151 citations

Journal ArticleDOI
01 Apr 1988-Nature
TL;DR: In this paper, a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) is presented.
Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

9,929 citations

Journal ArticleDOI
TL;DR: The WinGX suite provides a complete set of programs for the treatment of small-molecule single-crystal diffraction data, from data reduction and processing, structure solution, model refinement and visualization, and metric analysis of molecular geometry and crystal packing, to final report preparation in the form of a CIF.
Abstract: The WinGX suite provides a complete set of programs for the treatment of small-molecule single-crystal diffraction data, from data reduction and processing, structure solution, model refinement and visualization, and metric analysis of molecular geometry and crystal packing, to final report preparation in the form of a CIF. It includes several well known pieces of software and provides a repository for programs when the original authors no longer wish to, or are unable to, maintain them. It also provides menu items to execute external software, such as the SIR and SHELX suites of programs. The program ORTEP for Windows provides a graphical user interface (GUI) for the classic ORTEP program, which is the original software for the illustration of anisotropic displacement ellipsoids. The GUI code provides input capabilities for a wide variety of file formats, and extra functionality such as geometry calculations and ray-traced outputs. The programs WinGX and ORTEP for Windows have been distributed over the internet for about 15 years, and this article describes some of the more modern features of the programs.

9,479 citations

Journal ArticleDOI
10 Mar 1970

8,159 citations

Journal ArticleDOI
TL;DR: This review covers the literature published in 2014 for marine natural products, with 1116 citations referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms.

4,649 citations