1
72
M. Soroka and W. Goldeman
spectrum was measured. From this the ratio of unreacted 1-chloro-2,3-epoxypropane (multiplets at
2
2
.61, 2.90, 3.25, and 3.57), to the corresponding iodohydrin, 1-chloro-3-iodopropan-2-ol (multiplets at
.43, 3.91, 3.69, and 3.82), was estimated as 40 to 60 (based on integrals of these multiplets). There
were no peaks in the aromatic region on this spectrum indicating on the presence of o-phenylenedia-
3
mine. Then, the whole reaction mixture after reaction was titrated by 47.0 cm of a 1.00M solution of
Na S O in H O, what corresponds with yield of iodohydrin. The precipitate from inhomogenous
2
2
2
3
3
3
mixture was separated by suction, washed with 2ꢂ10cm H O, 5ꢂ10cm of saturated solution of
2
3
Na S O in H O, 3ꢂ10 cm H O, and dried on air to obtain 0.7 g of a dark red-brown solid identified
2
2
3
2
2
1
as crude phenazine-2,3-diamine by comparison of its FTIR and H NMR spectra with pure compound.
The organic phase from collected filtrates was evaporated to leave 2.2 g of oily residue identified as a
mixture of unreacted 1-chloro-2,3-epoxypropane and iodohydrin, as mentioned before.
Experiment 2. The Reaction of Iodine with Methyloxirane in Dichloromethane
in the Presence of 20 mol% o-Phenylenediamine
Methyloxirane (2.9 g, 50 mmol) was added to a stirred mixture of 1.08g o-phenylenediamine
3
ꢁ
10 mmol) in 50 cm CH Cl at about 20 C (water bath). Next, a solution of 12.7 g I (50 mmol) in
2 2 2
(
3
1
00 cm CH Cl was added dropwise (30 min) to the above mixture at the same temperature. The
2 2
reaction mixture darkened and a dark crystalline material precipitated. Then, the reaction mixture was
3
stirred overnight at the same temperature. A sample of 0.15 cm of the reaction mixture was taken,
ꢁ
3
1
evaporated in vacuo from a warm water bath (below 30 C), dissolved in 0.50 cm CDCl , and its H
3
NMR spectrum was measured. From this the corresponding iodohydrins, 1-iodopropan-2-ol and 2-
iodopropanol, in a 72=28 ratio (based on integrals of the corresponding methyl groups at 1.31 and
1
.90ppm) were identified and assayed. There were no peaks in the aromatic region on this spectrum
indicating on the presence of o-phenylenediamine. Then, the whole reaction mixture after reaction was
3
titrated by means of a 1.00 M solution of Na S O in H O. About 74 cm of this solution were
2
2
3
2
necessary to titrate the excess of iodine. Thus, as much as about 37mmol of the iodine remained
unreacted. Accordingly, the stoichiometry of the reaction of o-phenylenediamine to iodine is about 2:3.
3
The precipitate from inhomogenous mixture was separated by suction, washed with 2ꢂ10cm
H O, and dried on air to obtain 1.0 g (95%) of a red-brown solid identified as phenazine-2,3-diamine
2
1
1
by means of IR and H NMR spectra. H NMR (acetone-d ): ꢀ ¼ 5.61 (bs, 4H, NH ), 7.17 (s, 2H), 7.58
6
2
(
dd, 2H, J ¼ 3.4, 6.6 Hz), 7.97 (dd, 2H, J ¼ 3.4, 6.6 Hz).
The organic phase from the collected filtrates was separated and dried over Na SO (20 g), filtered,
2
4
ꢁ
and evaporated in vacuo from a warm water bath (below 30 C) to leave an oily residue (4.7g, 50%)
1
identified by means of its H NMR as the mixture of iodohydrins, 1-iodopropan-2-ol and 2-iodopro-
panol. No other peaks were observed on the spectrum.
Experiment 3. The Reaction of Bromine with 1-Chloro-2,3-epoxypropane in Dichloromethane
in the Presence of 20 mol% o-Phenylenediamine
1
-Chloro-2,3-epoxypropane (23.1 g, 250 mmol) was added to a stirred mixture of 5.4 g o-phenylene-
3
3
ꢁ
diamine (50 mmol) in 250 cm CH Cl at about 20 C (water bath). Next, a solution of 12.8 cm Br
2
2
2
3
250 mmol) in 50cm CH Cl was added dropwise (30 min) to the above mixture. The reaction was
(
2 2
slightly exothermic. The reaction mixture darkened and dark precipitate appeared. Then, the reaction
3
mixture was stirred 2 h at the same temperature, a sample of 0.15cm of the reaction mixture was
ꢁ
3
withdrawn, evaporated in vacuo from a warm water bath (below 40 C), dissolved in 0.50 cm CDCl ,
3
1
and its H NMR spectrum was measured. Except of peaks from the corresponding bromohydrin,
1
-bromo-3-chloropropan-2-ol (at 2.49, 3.58, 3,70, and 4.04), there were no other peaks, especially
in the aromatic region on the spectrum. Thus, no o-phenylenediamine was present in the reaction
mixture after reaction. Then, the reaction mixture was evaporated in vacuo from a warm water bath
ꢁ
3
below 40 C) to leave a dark oily residue, which was treated with 100cm ethyl ether. The dark
(
3
precipitate was separated by suction, washed with 3ꢂ10cm ethyl ether, and dried on air to obtain
9.5g of a dark solid insoluble in organic solvents or water containing huge amounts of Br (Beilstein
1
2