Control of Chemo- and Regioselectivity in the Palladium-Catalyzed Telomerization of Butadiene with Methanol − Catalysis and Mechanism

Hydrophobic 2,7-Octadienyl Ether-Cellulose Nanofibrils Using Butadiene Sulfone as the Dual Reagent and Medium

“…Trans adducts have been reported from telomerization of methanol due to energetically favored formation of a trigonal planar (1,6-diene) palladium complex. 42 Telomerization of 1,3-BD with phenol also generated >95% trans isomer of 1-phenoxyoctadiene. 58 Therefore, the strong evidence of cis isomer in ODE-NCs suggests that steric hindrance of the rigid crystalline surface of cellulose may have influence on the stereo-selectivity (Figure S8, 2′−4′) during the nucleophilic attack at the C-1 atom by OHs.…”

“…Interestingly, cis -alkene in ODE is an anomaly from the mechanism-based point of view. Trans adducts have been reported from telomerization of methanol due to energetically favored formation of a trigonal planar (1,6-diene) palladium complex . Telomerization of 1,3-BD with phenol also generated >95% trans isomer of 1-phenoxyoctadiene .…”

“…Telomerization of 1,3-BD with cellulose was optimized at varying quantities of the precursor BDS, expressed as the molar ratio of telomerized ODE to noncrystalline anhydroglucose unit (AGU) in cellulose. The reaction temperatures were set at 90 °C, the breakdown temperature of BDS into gaseous 1,3-BD and SO 2 , and 110 °C, the onset temperature of the Diels–Alder reaction between terminal alkene in the ODE group and 1,3-BD. , The optimal condition was evaluated by both quantities and qualities of organic-dispersible ODE-NCs in aprotic DMSO, DMF, CHCl 3 , and THF whose polarity and affinity to ODE-NCs should be relative to the extent of ODE substitution. The morphologies of organic dispersible ODE-NCs on hydrophilic mica and hydrophobic highly oriented pyrolytic graphite (HOPG) were observed by AFM.…”

Ligand-Controlled Regiodivergent Hydrosilylation of Conjugated Dienes Catalyzed by Mono(phosphine)palladium(0) Complexes

“…HSiPh 3 , HSiPh 2 Me, HSiPhMe 2 , HSiBnMe 2 , HSi­(OEt) 3 , HSiEt 3 , diallyl ether, and dienes 3a , 3b , 3m , 3n , 3o , and 3p were purchased from TCI or Aldrich. The mono­(phosphine)­palladium(0) complexes Pd­{η 2 :η 2 -(CH 2 CHCH 2 ) 2 O}­(PR 3 ) (R = Me ( 1a ), Et ( 1b ), Cy ( 1c ), OEt ( 1d ), O i Pr ( 1e ), Ph ( 1f ), OPh ( 1g )), , DSiPh 3 ( 2a - d ), HSiAr 3 (Ar = C 6 H 4 OMe-4 ( 2b ), C 6 H 4 Me-4 ( 2c ), C 6 H 4 Cl-4 ( 2d ), C 6 H 4 CF 3 -4 ( 2e )), and dienes 3c , 3d , 3e , 3f , 3g , 3h , 3i , 3j , 3k , 3l , and 3q were prepared by literature procedures with modification. 1 H, 2 H, and 13 C­{ 1 H} NMR spectra were measured on a 400 MHz (for 1 H) NMR spectrometer.…”

Tandem isomerization/telomerization of long chain dienes

“…However, until recently telomerization studies have been limited to C4-C5 dienes (butadiene and isoprene) due to their high reactivity (Benvenuti et al, 1999 ; Jackstell et al, 2007 ), limiting the range of feedstocks that can be used in the reaction. Following advances in the understanding of the bis-allyl monometallic mechanism (Behr and Urschey, 2003 ) including parallel catalytic cycles for the formation of lineal and branched telomerization products and dimerization by-products (Vollmuller et al, 2000 ; Jackstell et al, 2004 ) and the consequent catalysis development with the use of nucleophilic carbine (NHC) based catalysts (Clement et al, 2008 ), we have recently reported the telomerization of long-chain dienes (1,3-pentadiene and 1,3-hexadiene) with primary alcohols using homogeneous Pd catalysts with NHC ligands (Torrente-Murciano et al, 2010a ) adding to another previous example of long-chain dienes telomerization of C 10 terpene myrcene (Behr et al, 2010 ; Lopes et al, 2011 ).…”