The synthesis reported by Bodwell/Li (racemic, 2002) was a formal synthesis as it produced a compound already prepared by Rawal (no. 5 in the Rawal synthesis). The key step was an inverse electron demand Diels–Alder reaction of cyclophane 1 by heating in N,N-diethylaniline (dinitrogen is expulsed) followed by reduction of double bond in 2 to 3 by sodium borohydride / triflic acid and removal of the carbamate protecting group (PDC / celite) to 4.
The method is disputed by Reissig (see Reissig synthesis).