Solvents used for chromatography are quoted as volume/volume ratios. Analytical thin layer chromatography was performed using silica gel plates precoated with silica gel 60 F254 (0.2 mm) using UV light and 10% ethanolic solution phosphomolybdic acid dip to visualize the products. 1 H NMR spectra were recorded at 298 K unless otherwise stated using Varian VXR (200 MHz) spectrometers. Data is expressed in parts per million (ppm) downfield shift from tetramethyl silane with residual solvent as an internal reference ( δ 7.26 ppm for chloroform) and is reported as position ( δ in ppm), multiplicity (s = singlet, d = doublet, t = triplet, q = quartet = multiplet), coupling constant (J in Hz) and integration (number of protons). C NMR spectra were recorded at 298 K unless otherwise stated using Bruker