Turning 1-Alkenes Into 1,4-Diols

For organic chemists, adding reactive groups to alkenes is a common trick of the trade. Similarly, there are several ways to functionalize the carbon adjacent to an alkene group, which is known as an allylic carbon. But move along the chain just one more carbon—to the so-called homoallylic position—and converting a plain C–H into something more reactive becomes considerably more difficult. Now, chemists at the University of Illinois, Chicago, have come up with a way to activate this otherwise recalcitrant carbon (Nat. Chem. 2014, DOI: 10.1038/nchem.1841). Vladimir Gevorgyan and coworkers found they could convert 1-alkenes to 1,4-diols, thereby adding a reactive handle to the homoallylic position. The researchers first turn the terminal alkene into a hydrosilane. Then, with the help of an iridium catalyst, this hydrosilane reaches around to the homoallylic carbon to form a five-membered ring. Subsequent oxidation produces a 1,4-diol. The researchers demonstrated the 1,4-dioxygenation strategy on several alkene-containing natural products and derivatives.