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The reaction of aryl iodides, N‐tert‐butanesulfinamide, and allyl or homoallyl alcohol in the presence of a catalytic amount of Pd(OAc)2, NaHCO3 as a base, and TBAB leads to the formation of N‐tert‐butanesulfinyl imines in moderate yields. In this one‐pot process, a sequential Heck‐type arylation of the alkenol, isomerization of the double bond, and imine formation take place.

The reaction of aryl iodides, N‐tert‐butanesulfinamide, and allyl or homoallyl alcohol in the presence of a catalytic amount of Pd(OAc)2, NaHCO3 as a base, and TBAB leads to the formation of N‐tert‐butanesulfinyl imines in moderate yields. In this one‐pot process, a sequential Heck‐type arylation of the alkenol, isomerization of the double bond, and imine formation take place.

A novel transformation is reported for the reaction of terminal or internal alkynes with the nitrene precursor PhI=NTs (Ts=p‐toluenesulfonyl) in the presence of catalytic amounts of TpBr3Cu(NCMe) (TpBr3=hydrotris(3,4,5‐tribromo‐pyrazolylborate). Two products containing an imine functionality have been isolated from the reaction mixtures, identified as sulfinamides and isothiazoles. The former correspond to the formal reduction of the sulfone group into sulfoxide, whereas the latter involves the insertion of an alkyne carbon atom into the aromatic ring of the N‐tosyl moiety.

QC 20141205

Reported herein is a straightforward and enantiodivergent synthesis of both enantiomers of trifluoromethylated analogues of calcimimetic NPS R-569 in a highly estereoselective manner. The synthesis features a diastereoselective synthesis of the N-(isopropylsulfinyl)imine unit by the “DAG methodology” and a diastereoselective addition of Ruppert–Prakash's reagent to the imine as the key steps. No protecting groups were necessary, permitting an atom economic synthesis in only six steps. Further addition reactions of the CF3 anion to different N-(isopropylsulfinyl)imines were performed to demonstrate the suitability of the sulfinyl substituent to balance perfectly reactivity and diastereoselectivity.

The performed research demonstrates that important ligand classes can be synthesized on solid supports and can be used directly without purification to prepare asymmetric catalysts. For the catalyst system that was evaluated, the ligands prepared in parallel on support provided comparable enantioselectivities to purified ligands prepared individually over several steps in solution. Enantioselectivities greater than 90% ee were observed. These results hold promise for parallel synthesis and evaluation approaches in asymmetric catalyst optimization. A sulfinamide chiral auxiliary has also been developed. Auxiliary loading, diastereoselective transformations, and auxiliary removal all proceed in high yields. Auxiliary removal is accomplished by first activating the auxiliary linkage followed by nucleophilic release. Modification of the sulfinamide auxiliary as a support-bound linkage will allow the stereodefined synthesis of libraries of chiral compounds.