My PhD dissertation - Institut Fresnel

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(-)-N-{1-[(1S)-Phenylethyl]pyrrol-2-yl}succinimide (S-21): The amorphous solid formed
along with chloropyrrole (S-21) was collected by filtration and recrystallized from diethyl
ether to afford colorless needles; m.p. 148 - 149 °C; [ ] 20
α D = -143.0 (c = 1.0, tetrahydrofuran);
yield: 48.9 g (79%).
1 H NMR: δ = 7.3 (m, 3 H), 7.1 (m, 2 H), 6.89 (dd, J = 3.2, 1.9 Hz, 1 H), 6.28 (t,
J = 3.6 Hz, 1 H), 6.13 (dd, J = 3.8, 1.9 Hz, 1 H), 5.05 (q, J = 7.0 Hz, 1 H), 2.6 (m,
4 H), 1.77 (d, J = 7.0 Hz, 3 H) ppm.
13 C NMR: δ = 164.0, 142.4, 128.8, 127.7, 125.7, 118.8, 118.6, 108.0, 107.6, 55.4,
28.0, 22.2 ppm.
MS : 268 (23%, M + ), 164 (100%), 136 (12%), 105 (28%).
C16H16N2O2 (268.32) calcd. C 71.62% H 6.01%
found C 71.63% H 6.00%.
(+)-N-[(1R)-Phenylethyl]pyrrole-2-carboxylic acid (R-22): Potassium (7.6 g, 0.19 mol),
anhydrous magnesium chloride (9.7 g, 0.10 mol) and potassium iodide (5.3 g, 32 mmol) were
heated in refluxing tetrahydrofuran (0.15 L) for 90 min. A solution of
(+)-(1R)-2-chloro-N-(1-phenylethyl)pyrrole (R-20; 6.6 g, 32 mmol) in tetrahydrofuran
(5.0 mL) was then rapidly added and the mixture was heated for a further 3 h until gas
chromatography (30 m, DB-1, 175 °C) of an hydrolyzed sample did not show any trace of
starting material. At 25 °C, the resulting black slurry was poured on an excess of freshly
crushed dry ice and acidified to pH 1 with 2.0 M hydrochloric acid (50 mL). After decantation
of the reaction mixture and extraction with ethyl acetate (2 × 40 mL), the combined organic
layers were dried with sodium sulfate, filtered and concentrated to leave a brown oil which
slowly crystallized upon storage at -10 °C overnight. The obtained compound was sublimed
to give colorless needles; m.p. 89 - 91 °C (ref.
(c = 0.96, acetone); yield: 2.04 g (74%).
[ ]
[ ] 20
229 : m.p. 83.5 - 84.5 °C); α = 131.2
1 H NMR: δ = 7.3 (m, 3 H), 7.1 (m, 3 H), 7.03 (t, J = 2.2 Hz, 1 H), 6.56 (q,
J = 7.0 Hz, 1 H), 6.21 (dd, J = 3.9, 2.4 Hz, 1 H), 1.80 (d, J = 7.0 Hz, 3 H) ppm.
13 C NMR: δ = 165.9, 142.6, 128.6, 127.4, 126.7, 126.3, 121.3, 120.5, 108.8, 55.4, 22.0
ppm.
D