Cobalt-Catalyzed Biaryl Couplings via C–F Bond Activation in the Absence of Phosphine or NHC Ligands

A highly general and selective Co-catalyzed biaryl coupling through C–F cleavage under phosphine or NHC-free conditions was described. A broad range of aryl fluorides including unactivated fluorides as well as those with sensitive functionalities could couple with various Ti­(OEt)₄-mediated aryl Grignard reagents with high selectivity under the catalysis of CoCl₂/DMPU. Importantly, selective C–F bond activation couplings between two types of fluorines (difluorinated aromatics and on two different coupling partners) and in the presence of C–Cl or C–Br bonds could also be achieved

Unified Protocol for Cobalt-Catalyzed Oxidative Assembly of Two Aryl Metal Reagents Using Oxygen as an Oxidant

The first cobalt-catalyzed oxidative cross-coupling reaction of two aryl metal reagents is described. An equivalent amount of two aryl Grignard or lithium reagents, after mediation by an equivalent amount of simple ClTi­(OEt)₃, was facilely assembled under the catalysis of 1 mol % of CoCl₂/10 mol % of DMPU using oxygen. The cross-couplings between various aryl metal reagents, especially between two structurally similar aryl Grignard reagents, proceeded smoothly and selectively and, thus, provided a highly general and efficient method for the construction of biaryl compounds

Phenolate Enabled General and Selective Fe/Ti Cocatalyzed Biaryl Cross-Couplings between Aryl Halides and Aryl Grignard Reagents

The serendipitous addition of a phenolate to FeCl3/TMEDA/Ti­(OEt)4 enables a strong Fe/Ti cooperativity that can efficiently catalyze a general and selective biaryl-coupling reaction. In the absence of phosphine or NHC ligands, various aryl chlorides, bromides, and iodides can couple with a variety of common and Knochel-type aryl Grignard reagents. A wide range of sensitive functional groups in either coupling partner can be tolerated. This bimetallic cocatalysis not only remarkably extends the scope of Fe-catalyzed biaryl couplings but also provides a solution to the problem of functional group compatibility of Grignard reagents

Chemo- and Regioselective Alkylation of Pyridine <i>N</i>‑Oxides with Titanacyclopropanes

While titanacyclopropanes are used to react mainly with ester, amide, and cyano to undergo cyclopropanation, herein they react preferentially with pyridine N-oxide to accomplish C2–H alkylation beyond these functionalities with double regioselectivity. After being pyridylated at the less hindered C–Ti bond, the remaining C–Ti bond of titanacyclopropanes can be further functionalized by various electrophiles, allowing facile introduction of complex alkyls onto the C2 of pyridines. Its synthetic potential has been demonstrated by late-stage diversification of drugs

Additional file 1 of Small extrachromosomal circular DNA harboring targeted tumor suppressor gene mutations supports intratumor heterogeneity in mouse liver cancer induced by multiplexed CRISPR/Cas9

Additional file 1: Table S1. List of target locations with sgRNA sequences, primers for targeted PCR of 34 TSGs and Setd5, and outward primers for circularization junction of eccDNA. Table S2. Types, reads and frequencies of target site mutations in CRISPR/Cas9-induced mouse liver tumor tissues. Table S3. Types, reads and frequencies of target site mutations in single-cell clones derived from CRISPR/Cas9-induced mouse liver tumor tissues. Table S4. Types, reads and frequencies of target site mutations in parental single-cell clones and their subclones. Table S5. Types, reads and frequencies of target site mutations in single-cell clones at different time points of proliferation. Table S6. Types, reads and frequencies of target site mutations in 4 subcutaneous grafts and 2 single-cell clones derived from each of them. Table S7. Identification of eccDNAs from NIH-3T3, 1C3-1 and 6C7 by Circle-Seq. Table S8. Comparison of target site mutation types, reads and frequencies between gDNA and eccDNA