TLC plates were coated with silica gel G and developed in petroleum ether-diethyl ether (7 : 3, v/v). Spots were visualized by sprayng with 25 O/ o aqueous solution of perchlorid acid and subsequent charring at looo C. Silver-ion TLC was effected on40~20cmglassplateonsilicagel G,impregnated with 12 Yo silver nitrate.
Pertroleum ether-diethyl ether (23 : 2,v/v) solvent system was used for developing of plates. Spots were visualised by spraying the plates with 5 Yo alcoholic solution of 2: 7'-dichlorofluorescein and viewing under uv light.
Isolation of oil:
Powdered seeds were extracted repeatedly with light petroleum ether in a Sarhlet apparatus. The petrol extract was dried and the solvent was removed under reduced pressure. The seed and oil properties were determined by AOCS methods ' . The oil was saponified with aqueous ethanolic KOH. The unsaponifiable materials were removed by extraction with ether. The mixed fatty acids were obtained by the acidification of soap solution and were extracted with diethyl ether. Methyl esters were prepared by refluxing the mixed fatty acids for 1 hr. in a large excess of methanol containing catalytic amount of sulphuric acid.
Isolation of allene:
Freshly prepared methyl esters were fractionated on preparative silver-ion TLC plates (1 mm, 20 x 40 cm) impregnated with 12 Yo silver nitrate and developed in benzene. The allenic bands were scraped and extracted with diethyl ether on evaporation of solvent 24 Yo yield of pure allenic ester was obtained.