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The development of general and more atom-economical catalytic processes for Friedel–Crafts alkylations of unactivated arenes is an important objective of interest for the production of pharmaceuticals and commodity chemicals. Ferroceniumboronic acid hexafluoroantimonate salt (1) was identified as a superior air- and moisture-tolerant catalyst for direct Friedel–Crafts alkylations of a variety of slightly activated and neutral arenes with stable and readily available primary and secondary benzylic alcohols. Compared to the use of classical metal-catalyzed alkylations with toxic benzylic halides, this methodology employs exceptionally mild conditions to provide a wide variety of unsymmetrical diarylmethanes and other 1,1-diarylalkane products in high yield with good to high regioselectivity. The optimal method, using the bench-stable ferroceniumboronic acid salt 1 in hexafluoroisopropanol as cosolvent, displays a broader scope compared to previously reported catalysts for similar Friedel–Crafts reactions of...

The development of more general and efficient catalytic processes for Friedel-Crafts alkylations is an important objective of interest toward the production of pharmaceuticals and commodity chemicals. Herein, 2,3,4,5-tetrafluorophenylboronic acid was identified as a potent air- and moisture-tolerant metal-free catalyst that significantly improves the scope of direct Friedel-Crafts alkylations of a variety of slightly activated and neutral arenes, including polyarenes, with allylic and benzylic alcohols. This method also provides a simple alternative for the direct installation of prenyl units commonly found in naturally occurring arenes. Alkylations with benzylic alcohols occur under exceptionally mild conditions.

The optimal conditions A) are elaborated for the amination process and applied to a broad spectrum of (highly) functionalized boronic acids.

The synthesis of verubulin (Va) is studied on various pathways to avoid the use of the unstable 4-chloro analogue.

Treatment of vinyloxiranes with catalytic amounts of scandium triflate provides β,γ-unsaturated aldehydes.

Benzoic acids (I) efficiently promote the rearrangement to regioisomeric (E)-allylic alcohols including synthetically useful dienol and enynol derivatives.

The reaction of electron-rich heterocycles and electron-rich arenes is examined with different di- and trisubstituted propargylic alcohols.

A mild method is developed for the synthesis of a variety of tri- and tetraaryl methanes via reaction of benzylic alcohols with electron-rich arenes.

Pentafluorophenylboronic acid catalyzes the regioselective coupling of structurally diverse allylic alcohols with a variety of electron-rich aromatic and heteroaromatic substrates under ambient conditions. The commercially available catalyst is recoverable and air and moisture stable, and the reaction produces water as the only byproduct.

Radiohalogenated carbohydrates have been of significant interest to the Nuclear Medicine community since the success of 2-Deoxy-2-fluoro-glucose (FDG)/positron emission tomography (PET) to measure glucose metabolic rates in humans. This review of this important class of compounds will be written in two parts, and will concentrate on the chemistry. The first part will cover the development of FDG, the many attempts to synthesize other radiohalogenated PET and SPECT analogs, and future prospects of a SPECT analog. The second will cover the synthesis of other radio-halogenated carbohydrate compounds such as nucleosides, where the halogen is located on the sugar rings, as potential imaging or therapeutic agents. Copyright © 2002 John Wiley & Sons, Ltd.

A series of vinylchlorohydrins are resolved by enzymatic kinetic resolution. The resulting R-alcohols, obtained in up to 99% ee, are stereoselectively converted into vinyloxiranes in high yield. The S-acetates, obtained in up to 99% ee were either deprotected to S-alcohols, or cyclized directly to vinyl oxiranes under basic conditions, with moderate to no loss in ee. The results are consistent with a racemization mechanism involving reversible migration of the ace-tate during deprotection.