2000-43-3Relevant articles and documents
Substrate-Controlled Diastereoselective Synthesis of Sugar-Based Chlorinated Perhydrofuro[2,3-b]pyrans via Copper(I)-Catalyzed Radical Cyclization
Ram, Ram N.,Kumar, Neeraj,Gupta, Dharmendra Kumar
, p. 432 - 442 (2017)
The work describes the first copper(I) chloride/2,2′-bipyridine-catalyzed atom transfer radical cyclization (ATRC) of unsaturated carbohydrate-derived chloroacetals to generate chlorinated perhydrofuro[2,3-b]pyrans via an effective diastereoselective route. Various glycals (glucal, galactal and lactal) underwent the Ferrier rearrangement with 2,2,2-trichloroethanols to give acetal precursors stereoselectively, R-selective with galactal in contrast to S-selective with glucal. The radical cyclization of the Ferrier products occurred smoothly to afford cis-fused bicyclic products with the transfer of the chlorine atom at the non-anomeric carbon in the cyclized radical intermediate predominantly from the equatorial direction. The carbohydrate templates controlled the stereochemistry of both Ferrier rearrangement and ATRC steps. The stereostructures of the products were also supported by single crystal X-ray diffraction crystallography. The products possess biologically important structural segments such as a glycosidic linkage, a fused bicyclic acetal unit and a chlorosugar unit which are potential sources for biological studies and further synthetic elaborations. (Figure presented.).
A NEW ELECTROGENERATED BASE. CONDENSATION OF CHLOROFORM WITH ALIPHATIC ALDEHYDES
Shono, Tatsuya,Kashimura, Shigenori,Ishizaki, Kunihiko,Ishige, Osamu
, p. 1311 - 1312 (1983)
A novel base was generated by electrochemical reduction of 2-pyrrolidone in DMF, and this electrogenerated base (EGB) was effective to promote the condensation of chloroform with aliphatic aldehydes in good yields.
-
Reeve,Fine
, p. 1148 (1964)
-
Optical Resolution of Tertiary Acetylenic Alcohols and Secondary Alcohols by Complexation with Achiral Amines
Toda, Fumio,Tanaka, Koichi
, p. 1905 - 1908 (1986)
Partially resolved tertiary acetylenic alcohols and secondary alcohols were easily resolved completely by complexation with achiral amines such as 1,4-diazabicyclooctane (DABCO), N,N'-dialkylpiperazine, N,N,N',N'-tetramethylethylenediamine, and pyrazine, to give optically pure enantiomers.Interestingly, DABCO formed more stable complex with optically pure enantiomers but the other amines formed more stable complex with racemic compounds.
Synthetic process of rosone
-
Paragraph 0023; 0025; 0026; 0029; 0032; 0034; 0036, (2018/07/30)
The invention relates to a synthetic process of rosone. A solid super base is adopted as a catalyst during preparation of trichloromethyl benzyl alcohol, so that production of basic wastewater is avoided, product separation is facilitated, conversion rate of benzaldehyde is increased, the proportion of byproduct benzoic acid is reduced, and product yield is increased greatly and can be up to 95% or higher as the maximum.
One-Carbon Homologation of Primary Alcohols and the Reductive Homologation of Aldehydes Involving a Jocic-Type Reaction
Li, Zhexi,Gupta, Manoj K.,Snowden, Timothy S.
, p. 7009 - 7019 (2015/11/16)
(Trichloromethyl)carbinols, which are formed in one operation from either alcohols or aldehydes, can be converted into primary alcohols in a Jocic-type reaction involving LiBH4. The net result is a convenient two-step, one-carbon homologation of primary alcohols or a reductive one-carbon homologation of aldehydes featuring a broad substrate scope. The method is step-economical, and it nicely complements established one-carbon homologation strategies. (Trichloromethyl)carbinols, which are formed in one operation from either alcohols or aldehydes, can be converted into primary alcohols in a Jocic-type reaction involving LiBH4. The net result is a convenient two-step, one-carbon homologation of primary alcohols or a reductive one-carbon homologation of aldehydes featuring a broad substrate scope.
