20056-57-9Relevant academic research and scientific papers
Terminal-Selective Functionalization of Alkyl Chains by Regioconvergent Cross-Coupling
Dupuy, Stéphanie,Zhang, Ke-Feng,Goutierre, Anne-Sophie,Baudoin, Olivier
, p. 14793 - 14797 (2016/11/23)
Hydrocarbons are still the most important precursors of functionalized organic molecules, which has stirred interest in the discovery of new C?H bond functionalization methods. We describe herein a new step-economical approach that enables C?C bonds to be constructed at the terminal position of linear alkanes. First, we show that secondary alkyl bromides can undergo in situ conversion into alkyl zinc bromides and regioconvergent Negishi coupling with aryl or alkenyl triflates. The use of a suitable phosphine ligand favoring Pd migration enabled the selective formation of the linear cross-coupling product. Subsequently, mixtures of secondary alkyl bromides were prepared from linear alkanes by standard bromination, and regioconvergent cross-coupling then provided access to the corresponding linear arylation product in only two steps.
A 'meta effect' in the fragmentation reactions of ionised alkyl phenols and alkyl anisoles
Bouchoux, Guy,Sablier, Michel,Miyakoshi, Tetsuo,Honda, Takashi
scheme or table, p. 539 - 546 (2012/09/22)
The competition between benzylic cleavage (simple bond fission [SBF]) and retro-ene rearrangement (RER) from ionised ortho, meta and para RC 6H4OH and RC6H4OCH3 (R = n-C3H7, n-C4H9, n-C5H11, n-C7H15, n-C9H19, n-C 15H31) is examined. It is observed that the SBF/RER ratio is significantly influenced by the position of the substituent on the aromatic ring. As a rule, phenols and anisoles substituted by an alkyl group in meta position lead to more abundant methylene-2,4-cyclohexadiene cations (RER fragmentation) than their ortho and para homologues. This 'meta effect' is explained on the basis of energetic and kinetic of the two reaction channels. Quantum chemistry computations have been used to provide estimate of the thermochemistry associated with these two fragmentation routes. G3B3 calculation shows that a hydroxy or a methoxy group in the meta position destabilises the SBF and stabilises the RER product ions. Modelling of the SBF/RER intensities ratio has been performed assuming two single reaction rates for both fragmentation processes and computing them within the statistical RRKM formalism in the case of ortho, meta and para butyl phenols. It is clearly demonstrated that, combining thermochemistry and kinetics, the inequality (SBF/RER) metaorthopara holds for the butyl phenols series. It is expected that the 'meta effect' described in this study enables unequivocal identification of meta isomers from ortho and para isomers not only of alkyl phenols and alkyl anisoles but also in other alkyl benzene series. Copyright
Reactivity of mixed organozinc and mixed organocopper reagents: 6. Nickel-catalyzed coupling of methylarylzincs with primary alkyl halides; An atom-economic aryl-alkyl coupling
Pekel, ?zgen ?mür,Erdik, Ender
experimental part, p. 7087 - 7090 (2012/01/06)
A nickel-catalyzed process for the cross-coupling of mixed arylzincs and primary alkyl halides has been developed. The reaction of a methylarylzinc with a primary alkyl halide in THF in the presence of NiCl2/PPh 3 takes place with selective aryl transfer at room temperature in moderate yields. This protocol provides an atom-economic alternative to aryl-primary alkyl coupling using diarylzincs.
Alkylation of Aldehyde (Arenesulfonyl)hydrazones with Trialkylboranes
Kabalka, George W.,Maddox, John T.,Bogas, Ekaterini,Kelley, Shane W.
, p. 3688 - 3695 (2007/10/03)
(Arenesulfonyl)hydrazone derivatives of aryl aldehydes are readily alkylated by trialkylboranes in the presence of base to generate new organoboranes that may be converted to the corresponding substituted alkanes or alcohols depending upon the reaction conditions chosen. Both tosyl- and trisylhydrazone derivatives can be utilized in the reaction, which tolerates a variety of functional groups, making it a versatile alternative to both the Grignard and Suzuki-coupling reactions.
REDUCTIVE TRANSFORMATIONS WITH TRIMETHYLSILYL CHLORIDE-SODIUM IODIDE. A NEW SYNTHESIS OF 4H-1,3-OXAZINES
Ghera, Eugene,Maurya, Rakesh,Hassner, Alfred
, p. 4741 - 4744 (2007/10/02)
1-Arylalkenes and 1-arylalkanols are reduced to arylalkanes on heating with trimethylsilyl chloride/sodium iodide in CH3CN.Under similar conditions enones, dialkylated in the β-position of the double bond, give 4H-1,3-oxazines.
