1985-60-0Relevant academic research and scientific papers
A facile and highly efficient route to a traceless pi-arene chromium linker. Applications to synthetic and combinatorial chemistry.
Rigby,Kondratenko
, p. 3683 - 3686 (2001)
[reaction--see text] A simple and efficient method for the attachment of functionalized arene chromium carbonyls to a polymeric support has been developed. A highly efficient solid-phase synthesis of tertiary alcohols and esters was performed in a traceless manner using this strategy. The linker-fabrication protocol permits simultaneous immobilization of various substrates on the solid support.
Reductive Allylic Defluorinative Cross-Coupling Enabled by Ni/Ti Cooperative Catalysis
Lin, Zhiyang,Lan, Yun,Wang, Chuan
supporting information, p. 8316 - 8322 (2019/10/14)
Unactivated alkyl chlorides are abundant building blocks in organic synthesis, but they have been rarely engaged in cross-electrophile coupling. Herein, we report a Ni/Ti-cocatalyzed reductive allylic defluorinative cross-coupling between trifluoromethyl
Access to "friedel-Crafts-Restricted" tert -alkyl aromatics by activation/methylation of tertiary benzylic alcohols
Hartsel, Joshua A.,Craft, Derek T.,Chen, Qiao-Hong,Ma, Ming,Carlier, Paul R.
experimental part, p. 3127 - 3133 (2012/05/20)
Herein we describe a two-step protocol to prepare m-tert-alkylbenzenes. The appropriate tertiary benzylic alcohols are activated with SOCl2 or concentrated HCl and then treated with trimethylaluminum, affording the desired products in 68-97% yields (22 examples). This reaction sequence is successful in the presence of a variety of functional groups, including acid-sensitive and Lewis-basic groups. In addition to t-Bu groups, 1,1-dimethylpropyl and 1-ethyl-1-methylpropyl groups can also be installed using this method.
A new synthetic method for methyl ketones from carboxylic acids using metallic strontium and methyl iodide
Miyoshi, Norikazu,Matsuo, Tsuyoshi,Asaoka, Masashi,Matsui, Aki,Wada, Makoto
, p. 28 - 29 (2007/10/03)
Carboxylic acids reacted with metallic strontium and methyl iodide to give methyl ketones preferentially in moderate to good yields. Copyright
Cyanation of alcohols with diethyl cyanophosphonate and 2,6-dimethyl-1,4-benzoquinone by a new type of oxidation-reduction condensation
Masutani, Kouta,Minowa, Tomofumi,Hagiwara, Yoshiaki,Mukaiyama, Teruaki
, p. 1106 - 1117 (2007/10/03)
Cyanation of various alcohols by a new type of oxidation-reduction condensation is described. Primary alkyl diphenylphosphinites, 2,6-dimethyl-1,4-benzoquinone (DMBQ), and diethyl cyanophosphonate gave the corresponding nitriles in high yields. During the above experiment on cyanation of 4-phenylbutan-2-ol, the unexpected formation of a mixture of nitrile and isocyanide was observed. After careful examination of the reaction conditions, selective synthesis of isocyanides from secondary alcohols was successfully accomplished by the use of zinc oxide (ZnO) as an additive. Reaction of tertiary alcohols provided the corresponding isocyanides exclusively in the absence of an additive. Cyanation of optically active alcohols was tried in order to clarify the stereochemistry of this reaction, and the reaction was thus proved to proceed with the inversion of configuration.
DTBB-Catalysed dilithiation of styrene and its methyl-derivatives: Introduction of two electrophilic reagents
Yus, Miguel,Martínez, Pedro,Guijarro, David
, p. 10119 - 10124 (2007/10/03)
The reaction of styrene and some methyl-substituted styrenes 1 with lithium and a catalytic amount of 4,4′-di-tert-butylbiphenyl (DTBB) in the presence of several electrophiles [Me3SiCl, Me2CO, Et2CO, (CH2)5CO, Pr2CO], in THF, at temperatures ranging from -78 to 0°C, gave, after hydrolysis, products 2 resulting from addition of lithium to the olefinic double bond and successive trapping with the electrophilic reagent. When a carbonyl compound was used as electrophile, mixtures of the monoaddition-reduction compounds 3 and 4 were obtained as by-products, which could be easily separated from the diaddition products 2.
Highly regioselective reaction of zirconocene-alkene complexes with aldehydes or ketones
Suzuki, Noriyuki,Rousset, Christophe J.,Aoyagi, Koichiro,Kotora, Martin,Takahashi, Tamotsu,et al.
, p. 117 - 128 (2007/10/02)
Reactions of zirconocene-alkene complexes Cp2Zr(CH2=CHR)(PR'3) (R = H, Me, Et, SiR"3 or Ar) with aldehydes or ketones were investigated.Zirconocene-ethylene, -propylene or 1-butene complexes reacted with aldehydes or ketones at terminal carbons of alkenes to give the corresponding alcohols after hydrolysis with a high regioselectivity.A similar type of reaction product was also obtained by a reaction of zirconacyclopentanes with aldehydes.This reaction proceeded via β-β' carbon-carbon bond cleavage of zirconacyclopentanes.A reaction of zirconocene-vinylsilane complexes with ketones afforded 3-trimethylsilyl-1-oxa-2-zirconacyclopentanes with an excellent regioselectivity.Carbon-carbon bond formation occurred exclusively at the terminal carbon of vinylsilanes.Their corresponding γ-silylalcohols were obtained after hydrolysis.The products showed that vinylsilanes reacted with carbonyl compounds at the β-carbon to silyl group.It is in sharp contrast to the conventional reactions of vinylsilanes of which the α-carbon normally attacked electrophiles.The reactions of styrene and its derivatives with pentan-3-one on zirconium gave a mixture of two regioisomers.Substituents of alkenes tend to be in α-position to Zr in 1-oxa-2-zirconacyclopentanes.This orientation showed a different aspect of the formation of 1-oxa-2-zirconacyclopentanes from the alkene-alkene coupling reaction on zirconium.The regioselectivity of the reaction with carbonyl compounds decreased in this order; R = alkyl > silyl > aryl. Key words: Zirconium; Silicon; Metallocenes; Carbon-carbon bond formation; Aldehyde; Ketone
