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27th June 2012 @ 23:09
Single-crystal X-ray diffraction analyses were performed using a Bruker APEXII CCD diffractometer mounted at the window of a Bruker FR591 rotating anode (MoKα = 0.71073 Å) and equipped with an Oxford Cryosystems cryostream device. Data were processed using the Collect package and unit cell parameters were refined against all data. An empirical absorption correction was carried out using SADABS . The structures were solved by direct methods using SHELXS-97 and refined on Fo2 by full-matrix least-squares refinements using SHELXL-97. All non-hydrogen atoms were refined with anisotropic displacement parameters. All hydrogen atoms were added at calculated positions and refined using a riding model with isotropic displacement parameters based on the equivalent isotropic displacement parameter (Ueq) of the parent atom. Figures were produced using OLEX2
8th March 2012 @ 14:03
The X-Ray Powder Diffraction analysis was done with a Siemens X-Ray Diffractometer (model number D500) which was equipped with a two –circle goniometer. A scintillation counter in conjunction with a pulse height analyzer was used for counting. CuKα was obtained by operating the copper tube at 40V and 40mA using a graphite monochromator and passing the radiation through 1° divergent and scattering slits and a 0.15° receiving slit. Samples were between 2θ ranges from 2° to 53° at a rate of 1°/min (goniometer scanning speed). The X-Ray diffraction pattern obtained was analyzed using TOPAS software programme by Bruker AXS.
SAMPLE PREPARATION FOR X-RAY POWDER DIFFRACTION ANALYSIS: Each of the 4-substituted methylidene oxindoles was separately ground to obtain a fine particle size of about 10µ with pestle and mortar. About 300mg each of the ground samples was packed into a hole in the microscope slide and tightly pressed into the cavity with a spatula. A cover glass was placed over the packed cavity and the whole mount was inverted. The intact slide was slid out, giving a finished mount. The finished mount with exposed sample side up was placed in a sample holder of the goniometer and analyzed to obtain their corresponding diffractograms.

Siemens X-Ray Diffractometer
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8th March 2012 @ 14:02
Instrument Name: Agilent Technologies 1200 Series.
Pump: G1310A (ISO Pump), Serial number: DE62956516.
Detector: G1314B VWD, Serial Number: DE71359377.
Injector: G1328B Main Inj, serial Number: DE60557299.
Column Name: Zorbax Phenyl Column.
Length of Column: 25cm X 4.6mm internal diameter.
Pack Number: 880952-712.
The High Performance Liquid chromatography (HPLC) instrument described above was used to detect the presence of isomers and the degree of purity of the five synthesized methylidene oxindoles. The experimental condition set are shown below:
Mobile Phase: Methanol: Water 80:20 (v/v).
Stationary Phase: Methanol.
Flow Rate: 1.0ml/min.
Procedure: 10mg of each of the samples synthesized was weighed into 10ml volumetric flask and made up to the mark using methanol. Further dilution was made using 10ml of methanol: water 80:10 (v/v) for every 1ml of initial concentration. The diagram below shows the Agilent Technologies Series 1200 High Performance Liquid Chromatography.

Agilent Technologies 1200 Series High Performance Liquid Chromatography (HPLC)
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8th March 2012 @ 14:01
The Hot Stage Microscopy consist of a computer, microscope, hot stage made of two plates and camera and the instrument classification below shows the one used for the analysis of the five 4-substituted methylidene oxindolessynthesized.
Instrument Name: Mettler Toledo FP82HT Hot Stage.
Central Processor: Mettler Toledo FP90.
Serial Number: 5127091967.
Procedure: The top glass plate was cleaned to protect the optics of the microscope. The hot stage glass slide was cleaned and spatula was used to apply a tiny amount of sample (powder) 1cm below the edge of slide. The slide was tapped to knock off most of samples in order to a single well spaced layer of particles needed to run the experiment. The slide was then placed on top of bottom hot plate and used slide clip to hold it. The slide was positioned to be under the central hole of hot stage unit and adjusted to be viewed by microscope. The microscope was switched on and the coarse and fine focus was adjusted till a sharp image was formed. The full light intensity was used by adjusting the cross polarizer under the hot stage. The computer was used to set up the experimental conditions as shown below after the sample name (ID) on the image was written and the video saved.
Start temperature: 30°C
End Temperature: 300°C
Initial Isothermal: Not applicable.
The experiment was performed when communication between the computer and microscope was verified by checking if the frames were being counted on the computer image. The results obtained are shown in the next chapter and the instrument used is shown below.

Mettler Toledo FP82HT Hot Stage Microscope Melting Point Apparatus
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8th March 2012 @ 14:00
The presence of elements in each of these five methylidene oxindoles synthesized was analyzed qualitatively by using a Perkin-Elmer Paragon 1000 Attenuated Total Internal Reflectance (ATIR) Fourier Transform Infrared (FT-IR) Spectrometer.

Varian Excalibur (ATIR FT-IR) Spectrometer
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