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An enantioselective aldehyde α‐alkylation/semipinacol rearrangement was achieved through organo‐SOMO catalysis. The catalytically generated enamine radical cation serves as a carbon radical electrophile that can stereoselectively add to the alkene of an allylic alcohol and initiate ensuing ring‐expansion of cyclopropanol or cyclobutanol. This tandem reaction enables the production of a wide range of nonracemic functionalizable α‐quaternary‐δ‐carbonyl cycloketones in high yields and excellent enantioselectivity from simple aldehydes and allylic alcohols. As a key step, the intramolecular reaction was also successfully applied in the asymmetric total synthesis of (+)‐cerapicol. [ABSTRACT FROM AUTHOR]

A facile and efficient method to form a chiral multi-substituted 3H-spiro[benzofuran-2,1′-cyclopentane] structural unit has been developed via a one-pot [3+2] cyclization/semipinacol rearrangement cascade. A catalysis system of Cu(ii)/BOX has been used to efficiently construct a key stereogenic center via a cyclization between substituted benzoquinones and allylic alcohols affording the desired products in good yields and with excellent enantioselectivities and diastereoselectivities (21 examples; up to 67% yields; up to 92% ee and up to ＞20 : 1 dr). This method provides an alternative strategy for the synthesis of the corresponding bioactive molecules containing spiro[benzofurancyclopentane] skeleton units. [ABSTRACT FROM AUTHOR]

Over the past few decades, the semipinacol rearrangement has been widely applied in the field of organic synthesis. However, its catalytic asymmetric version has not caught much attention until the beginning of the 21st century. Significant breakthroughs have been made due to the efforts of organic chemists. These important progressions are summarized in this paper. [ABSTRACT FROM AUTHOR]

The novel method allows the synthesis of dialkylamino substituted malononitriles in low to good yields. [ABSTRACT FROM AUTHOR]

The title reaction is based on an efficient semipinacol rearrangement of β-aryl substituted olefinic aldehydes which provides the products in high yields and with very high enantioselectivities. [ABSTRACT FROM AUTHOR]

The formal synthesis of halichlorine (XII) has been conducted via intermediate (XI) (1.5% overall yield over 11 steps) starting from compound (X). [ABSTRACT FROM AUTHOR]

An abstract of the article "Copper-Catalyzed Intermolecular Azidocyanation of Aryl Alkenes" by L. Xu et al is presented.

The article presents steps of the chemical equations involved in the direct syntheses of spiro- and fused-hydrofurans.