provides polyfunctional phosphines in good yields. Especially attractive is the hydroboration/boron-zinc exchange sequence which allows the conversion of functionalized olefins into polyfunctional phosphines in a one-pot procedure. Several new chiral phosphines have been prepared starting from readily available chiral olefins (terpenes) and their efficiency in asymmetric hydrogenation reactions has been
Nitro-Power! An exceptionally general electrophilicamination of zinc organyl compounds was developed, and yields alkylated aromatic aminoboranes from commercially available nitroarenes. The partially reduced nitro group is directly engaged as an electrophilic nitrogen intermediate. The aminoboranes were reacted with electrophiles, thereby incorporating two different substituents at the N atom of the
A number of organozinc reagents was found to react with tetramethylthiuramdisulfide [(Me 2 NCS 2 ) 2 ] giving dithiocarbamates with complete retention of configuration in the case of chiral compounds.
Palladium-Catalyzed Cross-Coupling of Silyl Electrophiles with Alkylzinc Halides: A Silyl-Negishi Reaction
作者:Andrew P. Cinderella、Bojan Vulovic、Donald A. Watson
DOI:10.1021/jacs.7b04364
日期:2017.6.14
the first example of a silyl-Negishi reaction between secondary zinc organometallics and silicon electrophiles. This palladium-catalyzed process provides direct access to alkyl silanes. The delicate balance of steric and electronic parameters of the employed DrewPhos ligand is paramount to suppressing isomerization and promoting efficient and selective cross-coupling.
O<sub>2</sub>-Mediated Oxidation of Aminoboranes through 1,2-N Migration
作者:Marian Rauser、Daniel P. Warzecha、Meike Niggemann
DOI:10.1002/anie.201803168
日期:2018.5.14
In analogy to the classical reaction of C−B bonds with peroxides, the first oxidative functionalization of aminoboranes through a 1,2‐N migration was realized. Readily available aliphaticnitrocompounds are thereby transformed into N‐ and O‐functionalized hydroxylamines in a single synthetic operation. Addition of hazardous peroxides is avoided. Instead, the insertion of O2, as the terminal oxidant