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The stereochemistry of the diene must be taken into account to predict the stereochemistry of the product. An alkyne dicarboxylate was chosen as the dieneophile, as there is no stereochemistry in a triple bond (ester groups have been replaced with carboxylic acids for simplicity). For this trans,trans-diene, the phenyl groups end up beneth the face of the six-membered ring. In other words, this trans,trans-diene will give a product with two phenyl groups cis to one another.