6 research outputs found
Synthesis of Linear Allylsilanes via Molybdenum-Catalyzed Regioselective Hydrosilylation of Allenes
A simple
molybdenum-based catalytic system for hydrosilylation
of allenes has been developed. The reactions of mono- and disubstituted
allenes with secondary and tertiary silanes proceeded smoothly and
selectively to afford linear allylsilanes. The origin of the unprecedented
linear selectivity was investigated by density functional theory studies
to reveal that the reaction consists of the following steps: (1) concerted
hydromolybdation/Si–H oxidative addition from a MoÂ(CO)<sub>4</sub>/allene/silane adduct to form (Ď€-allyl)Âmolybdenum, (2)
allyl rotation from the initially formed (Ď€-allyl)Âmolybdenum
to a thermodynamically more stable isomer, and (3) reductive elimination
at the less-hindered allyl carbon to afford a linear allylsilane
Iron-Catalyzed <i>Ortho</i>-Allylation of Aromatic Carboxamides with Allyl Ethers
Arenes possessing an <i>N</i>-(quinolin-8-yl)Âamide directing
group are <i>ortho</i>-allylated with allyl phenyl ether
in the presence of an iron/diphosphine catalyst and an organometallic
base at 50–70 °C. The reaction proceeds via fast iron-catalyzed
C–H activation, followed by reaction of the resulting iron
intermediate with the allyl ether in Îł-selective fashion
Iron-Catalyzed C(sp<sup>2</sup>)–H Bond Functionalization with Organoboron Compounds
We report here that an iron-catalyzed
directed C–H functionalization
reaction allows the coupling of a variety of aromatic, heteroaromatic,
and olefinic substrates with alkenyl and aryl boron compounds under
mild oxidative conditions. We rationalize these results by the involvement
of an organoironÂ(III) reactive intermediate that is responsible for
the C–H bond-activation process. A zinc salt is crucial to
promote the transfer of the organic group from the boron atom to the
ironÂ(III) atom
Synthesis of Anthranilic Acid Derivatives through Iron-Catalyzed Ortho Amination of Aromatic Carboxamides with <i>N</i>‑Chloroamines
Arenes possessing
an 8-quinolinylamide group as a directing group
are ortho aminated with <i>N</i>-chloroamines and <i>N</i>-benzoyloxyamines in the presence of an iron/diphosphine
catalyst and an organometallic base to produce anthranilic acid derivatives
in high yield. The reaction proceeds via iron-catalyzed C–H
activation, followed by the reaction of the resulting iron intermediate
with <i>N</i>-chloroamine. The choice of the directing group
and diphosphine ligand is crucial for obtaining the anthranilic acid
derivative with high yield and product selectivity
Iron-Catalyzed Directed Alkylation of Aromatic and Olefinic Carboxamides with Primary and Secondary Alkyl Tosylates, Mesylates, and Halides
Alkenes, arenes, and heteroarenes
possessing an 8-quinolylamide
group as the directing group are alkylated with primary and secondary
alkyl tosylates, mesylate, and halides in the presence of FeÂ(acac)<sub>3</sub>/diphosphine as a catalyst and ArZnBr as a base. The reaction
proceeds stereospecifically for alkene substrates and takes place
without loss of regiochemical integrity of the starting secondary
tosylate, but with loss of the stereochemistry of the chiral center