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Reported here is the development of a class of chiral spirosilabiindane scaffolds by Rh‐catalyzed asymmetric double hydrosilation, for the first time. Enantiopure SPSiOL (spirosilabiindane diol), a new type of chiral building block for the preparation of various chiral ligands and catalysts, was readily prepared on greater than 10 gram scale using this protocol. The potential of this new spirosilabiindane scaffold in asymmetric catalysis was preliminarily demonstrated by development of the corresponding monodentate phosphoramidite ligands (SPSiPhos), which were used in both a Rh‐catalyzed hydrogenation and a Pd‐catalyzed intramolecular carboamination. [ABSTRACT FROM AUTHOR]

A tandem reaction of 4-(1-acetoxyallyl)-1-sulfonyl-1,2,3-triazole including formation of α-imino rhodium carbene, 1,2-migration of an acetoxy group and six electron electrocyclic ring closure was reported. The migration of the OAc group with excellent chemoselectivity was the crucial process, leading to the formation of 1,2-dihydropyridine specifically in up to 90% yield. Several transformations of the dihydropyridine product were also achieved illustrating the potential of the protocol in organic synthesis. Based on the observation of the intermediate, a plausible mechanism was proposed. [ABSTRACT FROM AUTHOR]

Highly functionalized 4-bromo-1,2-dihydroisoquinolines were synthesized from readily available 4-(2-(bromomethyl)phenyl)-1-sulfonyl-1,2,3-triazoles. A bromonium ylide is proposed as the key intermediate, which can be formed by the intramolecular nucleophilic attack of the benzyl bromide on the α-imino rhodium carbene formed in the presence of the rhodium catalyst. [ABSTRACT FROM AUTHOR]

Readily available 1-sulfonyl-1,2,3-triazoles were converted into α-imino carbenes in the presence of catalytic amounts of rhodium(II) salts. The carbenes underwent a tandem reaction with salicylaldehydes to provide a series of functionalized 2,5-epoxybenzo[ f][1,4]oxazepines in high yields. [ABSTRACT FROM AUTHOR]

α-Iminorhodium carbene, readily generated from N-sulfonyl-1,2,3-triazole,underwent cycloaddition and subsequentrearrangement with a nitrosobenzene derivative to afford N-acylamidine. The unprecedented C–C bond cleavage of α-iminocarbene was facilitated by the weaknessof the N–O bond. [ABSTRACT FROM AUTHOR]

The utility of the products is demonstrated by their use as tosylimino transfer agent for the formation of formimidamides. [ABSTRACT FROM AUTHOR]

α-Iminorhodium carbenoids generated from 1-sulfonyl 1,2,3-triazolewere applied to the 3 + 2 cycloaddition with ketene silyl acetal,offering a novel and straightforward synthesis of biologically interestingcompound 3-pyrrolin-2-one with broad substrate scope. [ABSTRACT FROM AUTHOR]

Highly functionalized isoquinolines are prepared from readily available aryl-sulfonyl-triazoles. [ABSTRACT FROM AUTHOR]

A diagram is presented which shows the synthesis of unsaturated ketone derivatives through sequential formation/rearrangement of rhodium-catalyzed sulfur ylide.

The article presents chemical equations related to the article "Synthesis of 3-Pyrrolin-2-ones by Rhodium-Catalyzed Transannulation of 1-Sulfonyl-1,2,3-triazole with Ketene Silyl Acetal" by R.-Q. Ran and others, published in "Organic Letters" in 2014.