Mono addition of HCl to unsymmetrical dienes generally produces four products – two 1,2-addition products and two 1,4-addition products. In some cases, such as the following, a 1,2-addition product and a 1,4-addition product may have the same structure, and thus only three distinct products are formed. Draw the reactant diene that forms the following three products, and identify the addition route that forms each product.