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Use of a rhodium catalyst with (R)-(S)-BPPFA ligand allows efficient synthesis of sila [n]helicenes via dehydrogenative silylation of CH bonds. By selecting the proper ligands, the current method provides the ability to prepare unsymmetrical sila [n]helicene derivatives without any oxidants. The resulting sila[6]helicene is a rare example of a five-membered ring-fused [6]helicene, which was isolated as a single pure enantiomer without substituents on the terminal benzene rings.Silicon-containing -conjugated molecules show promise as materials useful in the areas of electro-and photoluminescence. 1 The incorporated silicon atom has a significant impact on the energy levels of the frontier orbital, and that of the LUMO is effectively stabilized by the interaction between the low lying * orbital of two exocyclic -bonds of the silicon atom and the * orbital of the conjugated -system of the backbone. Catalytic dehydrogenative silylation of CH bonds is a straightforward, atom-efficient, and sustainable route toward these silicon-containing -conjugated molecules. 2-5 Since our first report in 2010 on the synthesis of silafluorenes, 3a rhodium-catalyzed dehydrogenative silylation has been developed for the synthesis of various silicon-containing -conjugated molecules, such as silicon-bridged p-terphenyl, 3a spirosilabifluorenes, 3b,3j benzosilolometallocenes, 3e-g dihydrobenzosilole, 3i and phenazasilines 3d (Figure 1). To further demonstrate the utility of this silylative cyclization, development of a robust catalyst system with improved reaction efficiency is highly desirable for the synthesis of more challenging siliconcontaining -systems. The present paper describes the synthesis of sila[n]helicenes (n = 4, 5 and 6) with uniquely merged -conjugated systems of helicene and silole. This study also demonstrates that the amino group-substituted (R)-(S)-BPPFA ((R)-N,N-dimethyl-1-[(S)-1',2-bis(diphenylphosphino)ferrocenyl]ethylamine) ligand is highly effective for the rhodiumcatalyzed dehydrogenative silylation of CH bonds.Helicene possesses a unique screw-shaped -system consisting of all ortho-annelated aromatic rings. 6 In addition to a unique function as an optoelectronic material, these compounds can be utilized as ligands and organocatalysts. 6c Despite their promising potential for functional materials, few [n]helicenes could allow customization of their properties, and dehydrogenative silylation with the activation of ubiquitous CH bonds is thought to allow a more straightforward approach. We previously reported that Wilkinson's catalyst, RhCl(PPh 3 ) 3 , is effective for the silylative cyclization of 2-(2-