146232-40-8Relevant academic research and scientific papers
A new method for synthesis of α,α-disubstituted carbonyl compounds from carbonyl compounds with one-carbon homologation through β-oxido carbenoid rearrangement as the key reaction
Miyashita, Kohsuke,Satoh, Tsuyoshi
, p. 5067 - 5080 (2005)
The addition reaction of carbonyl compounds with lithium α-sulfinyl carbanions of 1-chloroalkyl p-tolyl sulfoxides gave adducts, α-chloro β-hydroxy sulfoxides, in high to quantitative yields. The adducts were first treated with a base to give alkoxides, which were treated with i-PrMgCl or t-BuLi to give β-oxido carbenoids via a sulfoxide-metal exchange reaction. The β-oxido carbenoid rearrangement then took place to afford the enolates with one-carbon elongation. The enolate intermediates were found to be able to be trapped with electrophiles such as aldehydes, ethyl chloroformate, benzoyl chloride, haloalkanes to give α,α-disubstituted carbonyl compounds in moderate to good yields. This method provides a new and efficient way for synthesis of α,α-disubstituted carbonyl compounds from carbonyl compounds with one-carbon homologation in only two synthetic operations.
CF3CO2ZnEt-mediated highly regioselective rearrangement of bromohydrins to aldehydes
Wang, Zhihui,Li, Meiyi,Zhang, Wenqin,Jia, Jiangnan,Wang, Fei,Xue, Song
, p. 5968 - 5971 (2011/11/29)
A highly efficient and selective rearrangement reaction of bromohydrins to aldehydes mediated by CF3CO2ZnEt was described. The secondary and tertiary aldehydes were prepared under mild conditions in good to excellent yields (85-99%). The scope and limitations of this rearrangement process were also investigated.
Water-promoted cascade synthesis of α-arylaldehydes from arylalkenes using N-halosuccinimides: An avenue for asymmetric oxidation using Cinchona organocatalysis
Sharma, Abhishek,Sharma, Naina,Kumar, Rakesh,Sharma, Upendra K.,Sinha, Arun K.
supporting information; scheme or table, p. 5299 - 5301 (2010/01/31)
The direct oxidation of arylalkenes into α-arylaldehydes is achieved for the first time in water without relying on transition metal catalysts, and a novel organocatalytic enantioselective approach is also explored to provide up to 30% ee in initial investigations.
Et2Zn-mediated rearrangement of bromohydrins
Li, Lezhen,Cai, Peijie,Guo, Qingxiang,Xue, Song
, p. 3516 - 3522 (2008/09/20)
(Chemical Equation Presented) A simple and highly efficient method for the rearrangement of bromohydrins mediated by Et2Zn to synthesize carbonyl compounds was described. Various β-bromo alcohols were treated with 0.6 equiv of Et2Zn to form a zinc complex in CH 2Cl2 at room temperature for 2 h, followed by 1,2-migration to give the corresponding carbonyl compounds. This remarkable and clean rearrangement is general for acyclic and cyclic bromohydrins, and a variety of ring-expansive and -contractive carbonyl compounds were obtained in good to excellent yields according to the feature of the starting bromohydrins. The functional group tolerance of organozinc reagents in this reaction will be useful in organic synthesis. The scope and limitations of this rearrangement process were also investigated.
A new synthesis of α,α-disubstituted carbonyl compounds from carbonyl compounds with one-carbon homologation
Satoh, Tsuyoshi,Miyashita, Kohsuke
, p. 4859 - 4864 (2007/10/03)
Lithium α-sulfinyl carbanions of 1-chloroalkyl p-tolyl sulfoxides were reacted with carbonyl compounds to afford adducts in high to quantitative yields. The adducts were treated with t-BuMgCl or LDA to give magnesium or lithium alkoxides, which were treated with i-PrMgCl or t-BuLi to afford the enolate with one-carbon elongation through β-oxido carbenoids. The enolate intermediates were found to be able to be trapped with electrophiles to give α,α-disubstituted carbonyl compounds in moderate to good yields. As a whole, this procedure offers a new and good method for synthesis of α,α-disubstituted carbonyl compounds from carbonyl compounds with one-carbon homologation in only two synthetic steps.
New Method for Generation of β-Oxido Carbenoid via Ligand Exchange Reaction of Sulfoxides: A Versatile Procedure for One-Carbon Homologation of Carbonyl Compounds
Satoh, Tsuyoshi,Itoh, Norifumi,Gengyo, Kaoru,Takada, Sae,Asakawa, Naoyuki,et al.
, p. 11839 - 11852 (2007/10/02)
A new procedure for one-carbon homologation of carbonyl compounds is described.The method is based on the rearrangement of β-oxido carbenoid which is generated via the ligand exchange reaction of the sulfinyl group of α-chloro β-hydroxy sulfoxide with tert-butyllithium.Addition of the carbanion of aryl 1-chloroalkyl sulfoxides to carbonyl compounds gave the adducts in good yields.The β-oxido carbenoid rearrangement of the adducts gave one-carbon homologated carbonyl compounds having an α-alkyl substituent.A similar reaction of the adducts derived from carbonyl compounds with chloromethyl p-tolyl sulfoxide yielded a procedure for a methylene insertion.The stereochemistry of the β-oxido carbenoid rearrangenment is also discussed.
A novel method for generation of carbenoid from α-chloro sulfoxides: A new and versatile procedure for one-carbon homologation of carbonyl compounds to carbonyl compounds having an α-alkyl substituent
Satoh, Tsuyoshi,Itoh, Norifumi,Gengyo, Kaoru,Yamakawa, Koji
, p. 7543 - 7546 (2007/10/02)
Addition of the carbanion of 1-chloroalkyl p-tolyl sulfoxides to carbonyl compound gave the adducts, which were treated with a base followed by t-butyllithium to afford one-carbon homologated carbonyl compounds having an alkyl group at the α-position, via the β-oxido carbenoids, in moderate to good yields.
