Sulfenyiation of beta-Diketones Using C-H Functionalization Strategy

Sulfenylation of beta-diketones is challenging as beta-diketones undergo deacylation after sulfenylation in the reaction medium. The sulfenylation of beta-diketones without deacylation under metal-free conditions at ambient temperature via a cross dehydrogenative coupling (CDC) strategy is reported. The resultant products can be further manipulated to form alpha,alpha-disubstituted beta-diketones and pyrazoles

Synthesis of alpha-sulfenyl monoketones via a metal-free oxidative cross dehydrogenative coupling (CDC) reaction

alpha-Sulfenyl ketones are potential precursors which find a variety of applications in organic synthesis. Their typical synthesis requires pre-functionalized starting materials and two to three step synthetic sequences. In addition, the selective pre-functionalization of unsymmetrical ketones is a challenge, which limits the synthesis of the desired sulfenylated ketones. To overcome these disadvantages, a metal-free, convenient one-step strategy for synthesizing alpha-sulfenyl ketones at ambient temperature via a cross-dehydrogenative coupling (CDC) strategy has been developed with a broad substrate scope. Therefore, this CDC strategy for C-S bond formation is attractive and may find wide applications in organic synthesis

Pd-Boron-Catalyzed One Carbon Isomerization of Olefins: Water Assisted Process at Room Temperature

A palladium boronate/borane-system -catalyzed isomerization of olefins has been uncovered. An efficient Cy2 FG catalytic combination of Pd(OAc)(2)](3)-boronate-PCy3-enabled olefin isomerization at 80 degrees C has been investigated. Addition of water to the reaction showed a remarkable improvement and the isomerization occurred at ambient temperature. These catalytic systems function efficiently for the isomerization of functionalized as well as unfunctionalized olefms. The catalytic conditions demonstrate the involvement of both nonhydride and metal-hydride medium and can be switchable with water as an additive

Copper-Catalyzed Direct Transformation of Secondary Allylic and Benzylic Alcohols into Azides and Amides: An Efficient Utility of Azide as a Nitrogen Source

A mild and convenient method for the synthesis of amides has been explored by using secondary alcohols, Cu(ClO4)(2)6H(2)O as a catalyst, and trimethylsilyl azide (TMSN3) as a nitrogen source in the presence of 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) at ambient temperature. This method has been successfully adapted to the preparation of azides directly from their corresponding alcohols and offers excellent chemoselectivity in the formation of -halo azides and the azidation of allylic alcohols in the presence of a benzyl alcohol moiety. In addition, this strategy provides an opportunity to synthesize azides that can serve as precursors to -amino acids

Substituent-Directed Regioselective Azidation: Copper-Catalyzed C–H Azidation and Iodine-Catalyzed Dearomatizative Azidation of Indole

Azidation of indoles using iodine and copper bromide as catalysts under ambient reaction conditions is presented. The regioselectivity is directed by the substituent at the C3-position of indole. A radical stabilizing group such as an ester or ketone moiety at the C3-position of indole leads to azidation at the C2-position, whereas a less radical stabilizing group such as an alkyl or amide group at the C3-position of indole furnishes the 3-azidooxindole product. This protocol is mild and efficient to obtain several 2-azidoindole derivatives and 3-azidooxindole derivatives in moderate to good yields. The reaction conditions hold well for gram-scale synthesis