What does s- cis mean??
For the diene system,
S - cis conformation is Diels - Alder reaction prerequisite s - cis (s - cisoid) one of the conjugate dienes conformer due to carbon carbon free rotation of a single bond, and open the gratification of overlapping conformer s single bond single word (English), two double bonds in the same side, absence of corresponding s - s - cis trans stability, its extinction coefficient is less than 10000, with close dienes reagent for Diels - adriano ear reactions of carbonyl compounds have the conformer
For example, S-cis-1, 3-butadiene and S-cis-1-acetyl-2-methylcyclohexene
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