Metal-organic frameworks (MOFs) are the contemporary and swiftly growing class of crystalline coordination polymers having highly-ordered porous structure and high surface area. MOFs are composed of metal cations or clusters (Ni2+,Cr3+, Zr4+, etc) coordinated to the organic linker (carboxylates, phosphonates and N-donating ligands). The present study centers on the synthesis of high-valence V-MOF, MIL-47(V) with a focus on optimization of synthetic conditions in order to achieve high yield of crystalline MOFs. MIL-47(V) was prepared by the assembly of VO6 octahedra with 1,4-benzenedicarboxylic acid at 120°C at varying reaction times (24hrs, 48hrs, 72hrs and 96hrs). So obtained MOFs were comprehensively characterized by Fourier Transform-Infrared (FT-IR), Powder X-ray Diffraction (PXRD), and Scanning Electron Microscopy (SEM). It was found that MIL-47(96hrs.) displayed high crystallinity as demonstrated by its characteristics diffraction peaks resembling the simulated-MIL-47(V) pattern in PXRD analysis. Similarly, pristine and amine-functionalized low valence Ni-MOF, [Ni2(BDC)2(DABCO)] and [Ni2(NH2-BDC)2(DABCO)] were synthesized at 110°C. Both Ni-MOFs were comprehensively characterized using FT-IR, PXRD and SEM analysis.