Synthesis and structure of indenyl rhodium(I) complexes containing unsaturated phosphines: catalyst precursors for alkene hydroboration

Abstract

The indenyl compound (eta(5)-C(9)H(7))Rh(coe)(2) (1, coe = cis-cyclooctene) has been prepared as a thermally stable alternative to the diethylene derivative (eta(5)-C(9)H(7))Rh(eta(2)-H(2)C[double bond, length as m-dash]CH(2))(2). Compound 1 reacts with unsaturated phosphines Ph(2)PR (R = CH[double bond, length as m-dash]CH(2), 2; CH(2)CH=CH(2), 3; and C triple bond C-tert-Bu, 4) to give complexes of the type (eta(5)-C(9)H(7))Rh(Ph(2)PR)(2), where bonding occurs through the phosphorus atom. Addition of Ph(2)PC triple bond CPPh(2) to 1 gave the dimer [(eta(5)-C(9)H(7))Rh(micro-Ph(2)PC triple bond CPPh(2))](2) (5). Solution and solid state data showed that these new phosphine complexes have only a moderate amount of distortion within the indenyl ring. These compounds were found to catalyse the hydroboration of vinylarenes and the first example of an internal hydroboration of diphenylvinylphosphine has been reported.

Chemistry of N,S‐Heterocyclic Carbene and Metallaboratrane Complexes: A New η3‐BCC‐Borataallyl Complex

“…The C11C12 bond length of 1.389(7) Å is consistent with a double bond, similar to those observed in other rhodium π‐alkene complexes (Table 1). 27–32 Along with the CC distances, various structural parameters and 13 C NMR chemical shifts of a series of Rh‐alkene complexes are listed in Table 1, which corroborate well with those of compound 4 . The C13O2 distance (1.342(6) Å) is slightly shorter than a single bond length, which may be due to the participation in resonance of the ester group.…”

H2‐Acceptorless Dehydrogenative Boration and Transfer Boration of Alkenes Enabled by Zirconium Catalyst

“…With diphenylvinylphosphine,w hich was at ough substrate for other systems, 3y was produced in 93 %y ield. [24] Interestingly,o ur methodology also worked for long-chain alkene such as octene though 3z was obtained in lower yield and regioselectivity. Thus,o ur methodology not only achieved the first facile and direct dehydrogenative boration of alkenes with boranes but also yielded products that were not tolerated by other precious metal systems.…”

Alkenylphosphines: Applications in Synthesis, Catalysis and Coordination Chemistry

“…22) or a styrene derivative (eq. 32) [33]. In the latter case, the Markovnikov adduct was formed preferably (95/5 ratio for the Markovnikov and anti-Markovnikov adducts, respectively).…”

“…Contrarily to other results, a mixture of Markovnikov and antiMarkovnikov adducts 67 and 61 was formed; the main product was the diborated compound 68 (eq. 22) [33]. This latter arises from a competing dehydrogenative borylation process on 2 leading to an alkenylboronate ester, on which occurs the hydroboration reaction occurs.…”