Ynolates were found to react with alpha-alkoxy-, alpha-siloxy-, and alpha-aryloxyketones at room temperature to afford tetrasubstituted olefins with high Z selectivity. Since the geometrical selectivity was determined in the ring opening of the beta-lactone enolate intermediates, the torquoselectivity was controlled by the ethereal oxygen atoms. From experimental and theoretical studies, the high Z
Preparation of α-Oxygenated Ketones by the Dioxygenation of Alkenyl Boronic Acids
作者:Aditi S. Patil、Dong-Liang Mo、Heng-Yen Wang、Daniel S. Mueller、Laura L. Anderson
DOI:10.1002/anie.201202704
日期:2012.7.27
Two in two: Dioxygenation of alkenylboronicacids has been achieved with N‐hydroxyphthalimide. The two‐step process involves etherification of an alkenylboronicacid with N‐hydroxyphthalimide followed by a [3,3] rearrangement. The dioxygenated product can then be hydrolyzed to form either the corresponding α‐hydroxy ketone or the α‐benzoyloxy ketone.
Oxidation reactions catalysed by titanium- and chromium-containing silicalites
作者:Satya V. N. Raju、T. T. Upadhya、S. Ponrathnam、T. Daniel、A. Sudalai
DOI:10.1039/cc9960001969
日期:——
While the titanium silicalite-1 (TS-1)–tert-butyl hydroperoxide (TBHP) combination exhibits remarkable activity and selectivity in the oxidative cleavage of the C–C double bond of silyl enol ethers to produce dicarboxylic acids, the chemoselective oxidation of thioethers to sulfoxides without generation of sulfones is achieved using chromium silicalite-2 (CrS-2)–H2O2.
作者:Cihangir Tanyeli、Zerrin Çalişkan、Ayhan S. Demir
DOI:10.1080/00397919708005649
日期:1997.10
(+/-)-Mintlactone has been synthesized by applying a novel effective synthetic sequence. 4-Methylcyclohexanone was subjected to acetoxylation with Pb(OAc)(4). Hydrolysis followed by reaction with 2-chloroprogionyl chloride,then treatment with triethyl phosphite and, finally, Horner-Emmons-type intramolecular cyclization afforded (+/-)-Mintlactone.
CATALYTIC REDUCTIVE CLEAVAGE OF A B-O-4 BOND OF ETHERS OR POLYETHERS SUCH AS LIGNIN
申请人:KAT2BIZ AB
公开号:US20150218073A1
公开(公告)日:2015-08-06
The present invention relates to a method of cleaving a β-O-4 bond to the corresponding C—H bond in a substrate, by use of a hydrogen donor and a metal catalyst in a solvent. Thereby it is possible to depolymerize a polymer having a repeating β-O-4 bond.