thionyl chloride (or oxalyl chloride) has been used as an efficient and cheap acid activator for one-pot synthesis of β-lactams in good to excellent yields by reaction between imines and acids in the presence of triethylamine at room temperature.

Electrogenerated N-heterocyclic carbene can behave as an organocatalyst in the Staudinger reaction (from imine and acyl chloride) in a very polar solvent, such as an ionic liquid.

Staudinger reactions of Cy2BN3 with tri-substituted phosphines (R3P) yielded the boron-nitrogen-phosphorus linked systems Cy2BN=PR3 (R = Et, (t)Bu, Cy, Ph) (1a-1d respectively). Similarly, reaction of (C6F5)2BN3 with the phosphines P(t)Bu3, PPh3, Ph2PC≡CPh and Ph2PC≡CPPh2 yielded (C6F5)2BN=PR3 (2a-d respectively). In contrast, the reaction of (C6F5)2BN3 with Ph2P-C≡Cp-tol in the presence of exc...

Dynamic alterations in cell surface glycosylation occur in numerous biological processes that involve cell-cell communication and cell migration. We report here imaging of cell surface glycosylation in live mice using double click chemistry. Cell surface glycans were metabolically labeled using peracetylated azido-labeled N-acetylgalactosamine and then reacted, in the first click reaction, with...

The development of a lead-mediated α-arylation reaction between aryl azides and β-ketoesters or γ-lactams that facilitates the formation of 3H-indoles is disclosed. Twenty-five examples are included which demonstrate the generality of this reaction to access aryl azides bearing tetrasubstituted o-alkyl substituents. When paired with a Staudinger reduction, this reaction streamlines the synthesi...

The engineering of proteins can illuminate their biological function and improve their performance in a variety of applications. Within the past decade, methods have been developed that facilitate the ability of chemists to manipulate proteins in a controlled manner. Here, we present the traceless Staudinger ligation as a strategy for the convergent chemical synthesis of proteins. This reaction...

Bioorthogonal reactions are chemical reactions that neither interact with nor interfere with a biological system. The participating functional groups must be inert to biological moieties, must selectively reactive with each other under biocompatible conditions, and, for in vivo applications, must be nontoxic to cells and organisms. Additionally, it is helpful if one reactive group is small and ...

Asymmetric imidazolinium-dithiocarboxylates have been found for the first time to be highly selective catalysts; in the present case, the novel organocatalysts were able to catalyze the Staudinger reaction in up to 96% ee and 99% yield.