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This work reports a catalytic method that affords seven-membered carbon rings via expansion of β-ketoesters. This method tolerates alkynyl 1,2-diketones, common ynones, and alkynyl ketoesters, and affords the products with multiple functional groups.

Two unprecedented reactions using alkynyl 1,2-diketones and 1,3-dicarbonyls under phosphine catalysis have been achieved, furnishing a range of acyloxy allylidene malonates and γ-alkylidenebutenolides in good yields with high stereoselectivities.

We describe in this paper that using secondary OH as the kinetic resolution auxiliary group, a series of previously unavailable fluorinated fully-substituted carbon molecules can be obtained with excellent level of enantioselectivities.

The catalytic asymmetric construction of tetrasubstituted carbon stereocenters constitutes one of the most challenging research topics in organic synthesis, which further plays vital roles in diverse fields including medicinal and materials chemistry. In this context, the α-functionalization of β-ketocarbonyl compounds serves as one of the most frequently used strategies to address the issue. Compared to cyclic β-ketocarbonyls, the catalytic asymmetric α-functionalization of acyclic β-ketocarbonyls is more difficult but has gained enough progress over the last several decades. This review illustrates the recent advances in this field, including asymmetric fluorination with acyclic α-branched β-ketocarbonyl participation, Michael addition, amination, aldol reaction, α-alkylation, α-alkynylation, α-oxygenation, Mannich reaction, etc. Furthermore, a thorough survey of all these reactions indicates the existence of a general principle which is called the “Methyl Rule”. Alternative methods that can complement the deficiency of reports of the use of direct asymmetric catalysis are also presented.

1,3-Diketones with quaternary stereocenters are extraordinarily useful building blocks both in academic research and industrial production. However, the access to enantiopure acyclic 2,2-disubstituted 1,3-diketones has suffered from an extremely limited substrate scope and poor stereoselectivity control. In this paper, we report the successful organocatalytic kinetic resolution of 1,3-diketones with central quaternary stereocenters through the introduction of internal nucleophiles. Two basic resolution modes were established, allowing access to a broad scope of enantioenriched 1,3-diketones with quaternary stereocenters, together with a large variety of tetralone derivatives with vicinal fully substituted carbon centers, and both of them are not easily available via currently known methods. The inherent principles between the different combinations of ketone groups and the resolution patterns were also disclosed. This work constitutes a good complementary choice for the construction of 1,3-diketones with quaternary stereogenic centers and provides insightful information for further studies on diketone substrate-mediated intramolecular annulations and kinetic resolutions.

The discovery of new reaction modes mediated by easily available substrates is an important research topic in organic synthesis. Allyl ketones and related compounds have been demonstrated to undergo γ- or α-selective additions to different electrophiles. We disclose here the Brønsted base-catalyzed reaction of allyl ketones and alkynyl 1,2-diketones, which undergo a unique α-selective addition/intramolecular aldol-type annulation/C-C bond cleavage process, and a series of 2-acyloxycyclopent-3-enones can be obtained under very mild conditions.