We report here a C–H homoallylation reaction of aromaticketones with methylenecyclopropanes (MCPs) only using a catalytic amount of Fe(PMe3)4. A variety of aromaticketones and MCPs are applicable to the reaction to form ortho-homoallylated aromaticketones selectively via regioselective scission of the three-membered rings. The homoallylated products are amenable to further elaborations, providing
A Cu-catalyzed aminoboration of 1-methylenecyclopropanes with bis(pinacolato)diboron and O-benzoyl-N,N-dialkylhydroxylamines has been developed. The Cu catalysis provides a rapid and concise access to (borylmethyl)cyclopropylamines in a highly regio- and diastereoselective manner. The products obtained can be useful building blocks for the synthesis of potential antidepressants, trans-2-arylcyclopropylamine
Site- and Regioselective Silaborative C–C Cleavage of 1-Alkyl-2-Methylenecyclopropanes Using a Platinum Catalyst with a Sterically Demanding Silylboronic Ester
presence of a phosphine-free platinum catalyst, giving 3-substituted 2-boryl-4-silyl-1-butenes throughselectivecleavage of the less hindered proximalC–Cbond of the cyclopropane ring. The steric bulk of the silyl group of the silylboronic esters was critical for efficient formation of the silaboration products, and i-PrPh2Si–B(pin) was developed as a silylboronic ester of choice.
A copper-catalyzed ring-opening hydroamination of methylenecyclopropanes with polymethylhydrosiloxane and O-benzoylhydroxylamines has been developed. The cyclopropane C–C bond cleavage occurs selectively at the more congested proximal position, and the corresponding homoallylamines are obtained in good to excellent yields. The umpolung electrophilic amination strategy with the hydroxylamine derivatives