Cobalt(II) porphyrin complexes were shown to be general and efficient catalysts for selective cyclopropanation of alkenes with ethyl diazoacetate (EDA). The catalytic system can operate with alkenes as limiting reagents, requiring only stoichiometric amounts of EDA. The protocol is performed in one-pot fashion without the need of slow addition of EDA. The diastereoselectivity of the current system can be tuned by using different porphyrin ligands or additives, giving either trans- or cis-dominant cyclopropanes. The asymmetric cyclopropanation was also demonstrated with the use of chiral cobalt porphyrin complexes.

A procedure was developed for the preparation of beta-monobromo-tetraphenylporphyrin (BrTPP) in a greatly improved yield from the selective bromination of tetraphenylporphyrin (TPP) by NBS. BrTPP was successfully employed as a versatile synthon for convenient synthesis of a wide range of beta-monofunctionalized porphyrins with various heteroatom functionalities via palladium-mediated carbon-heteroatom bond formations. Examples include beta-amino, -amido, -oxo, and -mercaptoporphyrins from reactions with amines, amides, alcohols, and thiols, respectively. Applying the synthetic approach to chiral amides, beta-chiral porphyrins were effectively constructed.

A facile and practical methodology for the synthesis of synthetically useful diarylmethanol-based 1,4-diols and enantiomerically pure BINOL-derived diols with axial and sp(3)-central chirality has been developed through neighboring lithium-promoted [1,2]-Wittig rearrangement. The chirality transfer process shows a broad substrate scope in terms of the aromatic ether substituent, which allows access to a broad of range of chiral 1,1'-binaphthalene-2-α-arylmethanol-2'-ols with excellent enantioselectivities (>99 % enantiomeric excess) and yields (84-96 %). This should be considered as an available and attractive chiral source to design and prepare privileged ligands or catalysts.

[reaction: see text] meso-Aryloxy- and alkoxy-substituted porphyrins were conveniently synthesized by direct reactions of meso-halogenated porphyrins with alcohols via palladium-catalyzed C-O cross-coupling reactions. Using a combination of palladium precursor Pd(OAc)(2) or Pd(2)(dba)(3) and phosphine ligand DPEphos or Xantphos allowed both 5-bromo-10,20-diarylporphyrin and 5,15-dibromo-10,20-diarylporphyrin, as well as their zinc complexes, to be effectively coupled with a variety of alcohols to give the corresponding mono- and bis-substituted meso-aryloxy/alkoxyporphyrins in moderate to high yields under mild conditions.