An Efficient, Stereospecific Synthesis of the Dimer‐Selective Retinoid X Receptor Modulator (2E,4E,6Z)‐7‐ [5,6,7,8‐Tetrahydro‐5,5,8,8‐tetramethyl‐2‐(n‐propyloxy)naphthalen‐3‐yl] ‐3‐methylocta‐2,4,6‐trienoic Acid.