Sonogashira‐type cross‐couplings are one of the most significant alkynylations in organic chemistry. One of the first palladium‐catalyzed intramolecular Heck/Sonogashira reactions of alkenes with terminal alkynes is now reported. With this method, a variety of uniquely substituted chiral benzene‐fused heterocycles bearing a propargyl‐substituted all‐carbon quaternary stereocenter were obtained in a straightforward, high‐yielding, and highly stereoselective manner under mild conditions. Salient features of this process include the use of readily available substrates, high selectivities, a broad substrate scope as well as versatile product functionalizations.

A highly enantioselective palladium-catalyzed iodine atom transfer cycloisomerization of unactivated alkenes has been developed. This represents the first example of highly enantioselective carboiodination of olefin-tethered aryl iodides, which provides a perfect atom economy method to construct a series of optically active 2,3-dihydrobenzofuran, indolines and chromane bearing an alkyl iodide group in moderate to good yields. Moreover, the use of readily available starting materials, a broad substrate scope, high selectivity, mild reaction conditions, as well as versatile transformation of the product make this approach attractive. The mechanism of this Pd(0)-catalyzed asymmetric carboiodination of alkenes has been investigated with density functional theory.

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of main observation and conclusion A gold(I)-catalyzed asymmetric intermolecular tandem [3+3]-cyclization reaction of 2-(1-alkynyl)-2alken-1-ones with nitrones has been developed by using Ming-Phos as a chiral ligand. This method enables access to the stereodivergent synthesis of highly substituted furo[3,4-d][1,2]oxazines in excellent efficiency and stereoselectivity (up to 99% yield, 99% ee, >20 : 1 dr). Scheme 1 Previous results and this work on asymmetric [3+3] cycloaddition of 2-(1-alkynyl)-2-alken-1-ones with nitrones 578 www.cjc.wiley-vch.de

Sonogashira‐type cross‐couplings are one of the most significant alkynylations in organic chemistry. One of the first palladium‐catalyzed intramolecular Heck/Sonogashira reactions of alkenes with terminal alkynes is now reported. With this method, a variety of uniquely substituted chiral benzene‐fused heterocycles bearing a propargyl‐substituted all‐carbon quaternary stereocenter were obtained in a straightforward, high‐yielding, and highly stereoselective manner under mild conditions. Salient features of this process include the use of readily available substrates, high selectivities, a broad substrate scope as well as versatile product functionalizations.