Asymmetric Synthesis of the Northern Half C1−C16 of the Bryostatins
摘要:
[GRAPHICS]Starting from 8-oxabicyclo[3.2.1]oct-6-en-3-one and racemic 2,2-dimethyl-8-oxabicyclo[3.2.1]oct-6-en-3-one the C1-C16 segment of the bryostatins has been synthesized in 30 steps and 9% overall yield (17 steps longest linear sequence), Fragment coupling by dithiane strategy and protecting group manipulations provided an advanced chemodifferentiated northern half segment.
2-Methyl-2-alkenyl-substituted 1,3-dioxanes as odoriferous substances
申请人:Bertram Heinz-Jurgen
公开号:US20080070825A1
公开(公告)日:2008-03-20
The present invention relates to a compound of the formula (I)
wherein
R
1
denotes hydrogen or methyl, and R
2
and R
3
independently of one another denote methyl or ethyl.
本发明涉及一种化合物,其化学式为(I),其中R1代表氢或甲基,R2和R3分别独立地代表甲基或乙基。
PRODUCTION OF HYDROXY ETHER HYDROCARBONS BY LIQUID PHASE HYDROGENOLYSIS OF CYCLIC ACETALS OR CYCLIC KETALS
申请人:Billodeaux Damon Ray
公开号:US20120330069A1
公开(公告)日:2012-12-27
A liquid phase hydrogenolysis of acetal compounds such as cyclic acetals and cyclic ketals are fed to a reaction zone and reacted in the presence of a noble metal catalyst supported on a carbon or silica support to make hydroxy ether mono-hydrocarbons in high selectivity, without the necessity to use acidic co-catalysts such as phosphorus containing acids or stabilizers such as hydroquinone.
CATALYSTS FOR THE PRODUCTION OF HYDROXY ETHER HYDROCARBONS BY VAPOR PHASE HYDROGENOLYSIS OF CYCLIC ACETALS AND KETALS
申请人:Devon Thomas James
公开号:US20120330067A1
公开(公告)日:2012-12-27
Catalyst compositions of palladium supported on alumina or zirconium oxide supports having low or no silicon dioxide contents and having a specific surface area or modified with alkali, alkaline earth, or phosphine oxide compounds are selective in a vapor phase hydrogenolysis reaction to convert cyclic acetal compounds and/or cyclic ketal compounds in the presence of hydrogen to their corresponding hydroxy ether hydrocarbon reaction products.
PRODUCTION OF HYDROXY ETHER HYDROCARBONS BY VAPOR PHASE HYDROGENOLYSIS OF CYCLIC ACETALS AND KETALS
申请人:Devon Thomas James
公开号:US20120330066A1
公开(公告)日:2012-12-27
A vapor phase hydrogenolysis reaction to convert cyclic acetal compounds and/or cyclic ketal compounds in the presence of hydrogen to their corresponding hydroxy ether hydrocarbon reaction products using a supported noble metal catalyst. The hydrogenolysis reaction can be carried out in the vapor phase and in the absence of a polyhydroxyl hydrocarbon co-solvent.
NICKEL MODIFIED CATALYST FOR THE PRODUCTION OF HYDROXY ETHER HYDROCARBONS BY VAPOR PHASE HYDROGENOLYSIS OF CYCLIC ACETALS AND KETALS
申请人:Billodeaux Damon Ray
公开号:US20120330068A1
公开(公告)日:2012-12-27
Catalyst compositions of alumina supports containing palladium and nickel are selective in a vapor phase hydrogenolysis reaction to convert cyclic acetal compounds and/or cyclic ketal compounds in the presence of hydrogen to their corresponding hydroxy ether hydrocarbon reaction products.