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We herein present organocatalytic approaches to synthesize fluorinated and deuterated α-substituted phenylglycine derivatives. Whereas the addition of diethyl azodicarboxylate to fluorinated α-substituted aldehydes furnishes chiral non-racemic compounds, the use of chloramine-T as a nitrogen source represents a rapid access to sulfamidated fluorinated amino acid precursors. Additionally, further functionalization was achieved through the palladium-catalyzed coupling of a p-bromosubstituted aldehyde with a range of fluorine or deuterium-containing boronic acids. Oxidation of the aldehyde function and cleavage of the protection group of the nitrogen give way to the free fluorinated unnatural amino acids.

Cross-coupling reactions of Grignard reagents with functionalized aryl, heteroaryl, and sterically hindered aryl chlorides are reported. A protocol disclosing the coupling of a wide range of substr...

[Pd(NHC)(PR(3))] complexes were shown to be active catalysts in the dehydrogenation of ammonia borane and the subsequent hydrogenation of unsaturated compounds at very low catalyst loadings (0.05 mol% for some substrates).

A highly efficient catalytic system for the tandem dehydrogenation of ammonia borane coupled with hydrogenation of alkenes (I), enones (III), and alkynes (V) is described.

Studies towards the synthesis of the bacterial peptide deformylase (PDF) inhibitor fumimycin are reported. The synthetic approach features an organocatalytic access to the alpha,alpha-disubstituted amino acid unit and results in the synthesis of an advanced intermediate which already contains all functionalities of fumimycin.

The synthesis of (+/-)-methoxyfumimycin, a potential new bacterial peptide deformylase (PDF) inhibitor, is reported. To generate the stereogenic fully substituted carbon, the key step is a 1,2-addition of a methyl Grignard reagent to a ketimine. The overall synthetic strategy involves a Dakin oxidation of a vanillin derivative, Friedel-Crafts acylation, Claisen rearrangement, lactonization, and rhodium-catalyzed olefin isomerization.