A synthesis of homologous series of mesogenic 2-amino-5-alkkloxyphenyl-1,3,4-oxadiazoles were prepared by the oxidative cyclisation of alkyloxybenzaldehyde semicarbozones (4) using chloramines-T (CAT) as osidate via intramolecular cycloaddition reaction. The reaction proceeds in better yield (75-85%) giving the product as solid with low melting points. The optical texture studies have been carried out using Leitz polarizing microscope to identify the liquid crystalline phases at different temperatures and it is found that the synthesized compounds exhibit nematic (N), smectic C (Sm C), smectic I (Sm I) and smectic G (Sm G) phases, sequentially at different temperatures.