Ring Scission of Diastereomeric 4-Butylspiropentylcarbinyl Radicals as a Chemical Model for Identifying Enzyme-Catalyzed FAD Adducts Resulting from Spiropentylacetyl-CoA
作者:Lev Lis、Elena S. Koltun、Hung-wen Liu、Steven R. Kass
DOI:10.1021/ja0114862
日期:2002.2.1
4-dibutylspiropentanes (17a and 17b) with C(1) and C(2) symmetry. Each bromide was used to generate its corresponding spiropentylcarbinyl radical (18a and 18b) via its AIBN-initiated tri-n-butyltin hydride reduction. The radical-trapped products are identified, the preferred ring scission mode is identified (C1[bond] C2 bond cleavage), and the estimated rates for the ringopening of 4-butylspiropentylcarbinyl radical
A novel derivative of (―)-6,6-dimethylbicyclo [3.3.1]ept-2-ene-2-methanol is disclosed.
The compound of formula (I), which is an object of the present invention, is the derivative :a,a-dimethyl-5-hydroxy-3-cyclohexene-1,4-dimethanol.
The present invention further discloses the process for obtaining the compound of formula (I), which consists in preparing the (-)-6,6-dimethylbicyclo [3.3.1]ept-2-ene-2- methanol epoxide, thereafter hydrating the above compound and separating the compound of formula (I) from the hydration products. Finally, this invention comprises the pharmaceutical compositions containing the compound of formula (I) which possess a pharmacological mucosecretolytic activity.
Stereochemistry of allylic oxidation with selenium dioxide. Stereospecific oxidation of gem-dimethyl olefins
作者:Henry Rapoport、Uday T. Bhalerao
DOI:10.1021/ja00748a028
日期:1971.9
A One-Pot Multicomponent Coupling Reaction for the Stereocontrolled Synthesis of (<i>Z</i>)-Trisubstituted Allylic Alcohols
作者:Young K. Chen、Patrick J. Walsh
DOI:10.1021/ja0396145
日期:2004.3.1
In this Communication, we outline a new one-pot, multicomponent coupling reaction that allows easy access to (Z)-trisubstituted allylic alcohols. Our strategy is based on E to Z isomerization of the 1-bromo-1-dialkylvinylborane upon reaction with dialkylzinc reagents, and subsequent transmetalation to give (Z)-trisubstituted vinylzinc species. In situ trapping of the reactive vinylzinc intermediates with aldehydes furnished a series of (Z)-trisubstituted allylic alcohols. This method represents a viable alternative to the Still-Gennari modification of the HWE olefination reaction, and it has the advantage that it allows coupling of larger fragments.