We began our study by establishing a rational strategy to synthesize CBBC 2a from DBC 1a under mild conditions without the use of toxic heavy metals. This goal was achieved by employing internally hydroxy-substituted DBC derivative 3a (R = H) as an intermediate (Fig. ; reactions A and B). The ruthenium-catalyzed cis-dihydroxylation of DBC 1a with NaIO4 as a terminal oxidant proceeded smoothly at room temperature to afford 3a in 95% yield (reaction A). The organoiodine(III)-catalyzed oxidative glycol cleavage (34) of 3a proceeded smoothly using a catalytic amount of iodobenzene and a stoichiometric amount of m-chloroperoxybenzoic acid (m-CPBA) to furnish CBBC 2a in 92% yield (reaction B). Importantly, both reactions A and B can be readily scaled up to provide 8.7 g of 3a and 3. Various brominated DBC derivatives also engaged in this transformation and furnished the corresponding CBBCs 2f-2i in 63-86% yield over two steps. These brominated CBBC derivatives are valuable precursors for the construction of elaborate frameworks.