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Research has been conducted on aromatic bromides. Tha authors describe palladium-catalyzed amination of these compounds with hindered N-alkyl-substituted anilines carried out via the use of palladium(I) tri-tert-butylphosphine bromide dimer.

Suitably protected oxygenated trienes were successfully used in an application to the first synthesis of the antiulcerogenic terpene glycoside (-)-cassioside isolated from the aqueous extract of the Cinnamomi cortex. A synthetic sequence to (-)-cassioside, consisting of nine steps with an overall yield of approximately 14%, was achieved with the successful implementation of the asymmetric Diels-Alder reaction of TIPS-protected trienolsilyl ethers catalyzed by TiCl4-SbPh3 coupled with glycosidation using p-methoxybenzyl-protected carbohydrate sulfoxides.

Reports on the successful use of suitably protected oxygenated trienes in an application to the first synthesis of the potent antiulcerogenic terpene glycoside (-)-cassioside, isolated from the aqueous extract of the Cinnamoni cortex and characterized by a Japanese group in 1988. Enantioselective construction of the quaternary center; Stereochemistry.

A diastereoselective rhodium-catalyzed arylation of N-(tert-butanesulfinyl)imines with sodium tetraarylborates is described. This method is general for constructing various chiral α-branched amines and 2-substituted pyrrolidines with high diastereoselectivity. A practical asymmetric approach to access chiral amines has been developed involving the use of air-stable Rh catalysts and reagents and in the absence of an external ligand.

A highly regio- and diastereoselective reduction of various N-tert-butanesulfinyl ketimine esters with L-Selectride resulting in the formation of α-amino acids is reported. This method is quite general and also practical for the preparation of both enantiomers of aryl or aliphatic α-amino acids in high yields., (© 2011 American Chemical Society)

A new and general method for asymmetric synthesis of either enantiomer of 2-substituted pyrrolidines from a single starting material is described. Reductive cyclization of (S(S))-gamma-chloro-N-tert-butanesulfinyl ketimines with LiBHEt(3) in THF at -78 to 23 degrees C afforded (S(S),R)-N-tert-butanesulfinyl-2-substituted pyrrolidines in excellent yields (88-98%) and with high diastereoselectivity (99:1). The diastereoselectivity is controlled effectively by the choice of reducing agent. Thus, the corresponding epimers of (S(S),S)-2-substituted pyrrolidines were synthesized in good yields (87-98%) and with high diastereoslectivity (1:99) by simply switching the reducing agent from LiBHEt(3) to DIBAL-H/LiHMDS. Deprotection of N-tert-butanesulfinyl-2-substituted pyrrolidines using 4 N HCl in dioxane and MeOH gave the corresponding enantiomers of 2-substituted pyrrolidines in quantative yield. This method was found to be effective for a variety of substrates including aromatic, heteroaromatic, and aliphatic substituents. Extension of this methodology to the formation of 2-substituted piperidines is also illustrated. Reductive cyclization of (S(S))-delta-chloro-N-tert-butanesulfinyl ketimine with LiBHEt(3) in THF at -78 to 23 degrees C or DIBAL-H/LiHMDS in toluene at -78 to 0 degrees C afforded the (S(S),R)-N-tert-butanesulfinyl-2-substituted piperidines in excellent yield (98%) and with high diastereoselectivity (99:1) or (S(S),S)-N-tert-butanesulfinyl-2-substituted piperidines in good yield (98%) and with high diastereoselectivity (1:99), respectively.