反应详情

2,4-Dimethyl-5-carbethoxy-pyrrole (1.64 g), acetic acid (25 ml), aqueous hydriodic acid (25 ml) and paraformaldehyde (0.589g), were heated at 95°-100° C. for three hours under nitrogen with stirring. The work up was the same as that of 2,3,4-trimethyl-5-carbethoxy-pyrrole in Example 4 except the 2 × 75 ml of ether was used and care was taken to avoid exposure of the product to air. It was purified by distillation (10 mm, 60° C.) to give 0.628 g (52%), m.p. 106°-108° C. (lit4 m.p. 111°-112° C.).

1. distillationIt was purified by distillation (10 mm, 60° C.)
2. customto give 0.628 g (52%), m.p. 106°-108° C. (lit4 m.p. 111°-112° C.)