Structural, Spectral, Biological and Electrochemical Studies Of Some ...

an additional 22 minutes. The crystals were collected by filtration, washed well with
water and dried under a heat lamp. The crude product was recrystallised from a
mixture of 50 mL of ethanol and 25 mL of water. This gave 10.8 g (81%) of stout
colourless rods of 4-methyl-4-phenyl-3-thiosemicarbazide, mp 124°C.
Step.3:- Synthesis of morpholine-4-thiocarboxylic acid 2 [1-(2-pyridinyl) ethylidene]
hydrazide, HL4M.
Fig. 2.1 Structural formula ofHL4M
A solution 1 g (5.52 mmol) of 4-methyl-4-phenyl-3-thiosemicarbazide.in 5 mL of
acetonitrile was treated with 480 mg (5.52 mmol) of morpholine and 668 mg (5.52
mmol) of 2-acetylpyridine..The solution was heated at reflux for 15 minutes. The
solution was chilled and the crystals that separated were collected and washed well
with acetonitrile. This afforded 850 mg (58%) ofstout yellow rods ofmorpholine-4­
thiocarboxylic acid 2[1-(2-pyridinyl) ethylidene] hydrazide, Fig. 2.1. The compound
was recrystallised from methanol, mp 188°C.
Synthesis of pyrrolidine-4-thiocarboxylic acid 2[1-(2-pyridinyl) ethylidene]
hydrazide, HL4P
Fig. 2.2 Structuralformula ofHL4P
A solution 1 g (5.52 mmol) of 4-methyl-4-phenyl-3-thiosemicarbazide.in 5 mL of
acetonitrile was treated with 392 mg (5.52 mmol) of pyrrolidine and 668 mg (5.52
18