3-Benzyl-9-phenyl-2-tosyl-2,3,3a,4,9,9a-hexa­hydro-1H-pyrrolo[3,4-b]quinoline

In the title compound, C31H30N2O2S, the pyrrolidine ring adopts a twist conformation while the tetra­hydro­pyridine ring is in a half-chair conformation. The two rings are trans-fused. The pyridine-bound phenyl ring forms dihedral angles of 17.7 (1) and 48.1 (1)°, respectively, with the tosyl and benzyl phenyl rings. The mol­ecular structure is stabilized by an N—H⋯π inter­action involving the benzyl phenyl ring. In the crystal structure, mol­ecules translated by one unit along the a axis are linked into chains by C—H⋯π inter­actions involving the benzene ring of the tosyl group

3-Benzyl-7-meth­oxy-9-phenyl-2-tosyl-2,3,3a,4,9,9a-hexa­hydro-1H-pyrrolo[3,4-b]quinoline

In the title compound, C32H32N2O3S, the pyrrolidine ring adopts an envelope conformation with the methine C atom nearest to the phenyl ring as the flap atom. The tetra­hydro­pyridine ring has a half-chair conformation. The two rings are trans-fused. The phenyl ring bound to the tetra­hydro­pyridine is oriented almost perpendicular [dihedral angle = 86.35 (10)°] to the fused benzene ring. The dihedral angle between the benzyl­phenyl ring and the sulfonyl-bound phenyl ring is 69.43 (10)°. A very weak N—H⋯π inter­action is observed in the mol­ecular structure. In the crystal, mol­ecules translated one unit along the b axis are linked into C(10) chains by C—H⋯O hydrogen bonds; adjacent chains are linked via C—H⋯π inter­actions, forming a two-dimensional network parallel to the bc plane

4,4-Dimethyl-2-tosyl-1,2,3,3a,4,11b-hexa­hydro-11H-pyrrolo[3,4-c]pyrano[5,6-c]chromen-11-one 0.125-hydrate

In the title compound, C23H23NO5S·0.125H2O, the pyrrolidine ring has a twist conformation and the dihydro­pyran ring adopts a half-chair conformation; the two rings are cis-fused. The mol­ecule adopts a folded conformation. The sulfonyl-bound phenyl ring and the pyran ring of the coumarin ring system are stacked over one another, with a centroid–centroid distance of 3.7470 (7) Å; the dihedral angle between the two rings is 18.93 (2)°. An intra­molecular C—H⋯O hydrogen bond is observed. The solvent water mol­ecule, lying on a twofold rotation axis, is only partially occupied with an occupancy of 0.125 (relative occupancy with respect to the main molecule) and is involved in O—H⋯O and C—H⋯O hydrogen bonding

3-Benzyl-7-bromo-9-phenyl-2-tosyl-2,3,3a,4,9,9a-hexa­hydro-1H-pyrrolo[3,4-b]quinoline

In the title compound, C31H29BrN2O2S, the pyrrolidine ring is in a twist conformation and the tetra­hydro­pyridine ring adopts an envelope conformation with the methine C atom adjacent to the NH group as the flap atom; the two rings are trans-fused. The bromo­benzene ring and the nearest phenyl ring form a dihedral angle of 82.72 (10)°. The benzyl phenyl and the tosyl phenyl rings are oriented at a dihedral angle of 75.57 (11)°. An intra­molecular N—H⋯π inter­action is observed. In the crystal, mol­ecules are linked into chains running along [101] by C—H⋯O hydrogen bonds and the chains are cross-linked via weak C—H⋯π inter­actions

1-Ethyl-2-tosyl-4,4,6-trimethyl-2,3,3a,4-tetra­hydro-1H-pyrrolo[3,4-c]pyrano[6,5-b]quinoline-11(6H)-one monohydrate

In the title compound, C26H30N2O4S·H2O, the pyrrolidine and dihydro­pyran rings adopt envelope conformations and they are cis-fused. The sulfonyl group has a distorted tetra­hedral geometry. In the crystal structure, the mol­ecules are linked into a ribbon-like structure along the a axis by O/C—H⋯O hydrogen bonds involving water mol­ecules and C—H⋯π inter­actions involving the sulfonyl-bound phenyl ring. Adjacent ribbons are cross-linked via C—H⋯O hydrogen bonds involving a sulfonyl O atom and C—H⋯π inter­actions involving the pyridinone ring

Seven papers on fused-ring heterocyclic ketones containing an N-tosyl­pyrrolo­[3,4-c]pyrano moiety. Corrigenda

Corrigenda to Acta Cryst. (2007), E63, o4363, o4364, o4434–o4435, o4436–o4437, o4438, o4489–o4490 and o4491–o4492

THE EFFECT OF JATROPHA BLEND FOR DUAL INHIBITION APPLICATION

The oil and gas industry is exposed to fow assurance issues such as wax deposition and scale precipitation. The sector has been tackling this issue using the chemical method while extensive research is being conducted to fnd an efective solution. The conventional method is costly and not eco-friendly. This paper focuses on using Jatropha curcas seed oil (JSO) blended with Ethylenediaminetetraacetic acid (EDTA) as a promising dual inhibition application solution to counter wax and scale deposition simultaneously. The experiment manipulates the temperature and concentration to determine the efciency of the inhibitor and its capability to improve fowability. Flowability and jar tests were conducted to analyze the blend’s ability to act as a dual inhibitor. The results prove that the blend of JSO and EDTA at the concentrations of 3 wt% and 1 wt%, respectively, at 70°C showcased a robust result in wax inhibition by enhancing the fowability of the crude oil. On the other hand, efective scale inhibition is achieved when 1 wt% JSO is blended with 1 wt% of EDTA at 27°C. The results obtained signifes the compatibility of JSO and EDTA blend in dual inhibition application when optimal temperature and concentration are achieved. Dual inhibition application is expected to be a one-stop solution for both wax and scale precipitation that is economically viable and safe

7-Bromo-3-ethyl-9-phenyl-2-tosyl­pyrrolo[3,4-b]quinoline

In the title compound, C26H27BrN2O2S, the pyrrolidine ring adopts a twist conformation, while the tetra­hydro­pyridine ring is in a half-chair conformation. The two rings are trans-fused. The dihedral angle between the phenyl ring and the sulfonyl-bound benzene ring is 22.83 (7)°. N—H⋯O hydrogen bonds link the mol­ecules into a chain along the b axis, and the chains are cross-linked into a three-dimensional network by a C—H⋯π inter­action and a weak π-π inter­action between the sulfonyl-bound benzene rings; the centroid–centroid distance is 3.6957 (8) Å

CHARACTERIZATION OF MALAYSIAN JATROPHA SEED OIL USING FTIR AND GCMS

Flow assurance problems such as wax deposition impacted the oil and gas industry in various points of oil transport hence a cure is widely researched. This paper aims to establish a cure by using Jatropha curcas seed oil (non-edible) originated from Malaysia and its sustainability as a wax inhibitor component. Extraction and characterization of Jatropha seed oil using Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatography-Mass Spectrometry (GCMS) were conducted to identify the properties of Jatropha seed oil such as the presence of oleic acid which is the main component required in wax inhibitor. Jatropha seed oil extraction was conducted using a soxhlet extractor and n-Hexane solvent which was heated at 70°C. The obtained results illustrated that at the peak of 1746.48 cm–1, FTIR analysis indicated the presence of C=O stretching carboxyl which was the ester fatty acid group while at a retention time of 36.834 min, 44.91% of the oleic acid was present via GCMS analysis. The analysis revealed the presence of high oleic acid in Jatropha seed oil has great potential as wax inhibitor to improve the flowability retarded by wax precipitation