A new method for the preparation of olefins from vicinal diols
作者:Mustafa Adiyaman、Young-Ju Jung、Seongjin Kim、Goutam Saha、William S. Powell、Garret A. FitzGerald、Joshua Rokach
DOI:10.1016/s0040-4039(99)00675-9
日期:1999.5
A novel method is reported for the transformation of vicinal diols to olefins. This methodology consists in the conversion of iodothiocarbonates such as 16 to olefin 17 with phenyl lithium in excellent yield. Compounds 7 and 12 were prepared by this methodology in order to determine if they would be recognized by the enzymes, 5-lipoxygenase and 15-lipoxygenase, respectively.
Hydroboration. 86. Convenient conversion of aldehydes and ketones into the corresponding alkenes via hydroboration of their enamines. A remarkably simple synthesis of either (Z)- or (E)-alkenes
作者:Bakthan Singaram、Milind V. Rangaishenvi、Herbert C. Brown、Christian T. Goralski、Dennis L. Hasha
DOI:10.1021/jo00004a038
日期:1991.2
Aldehydes and ketones are converted into the corresponding alkenes via hydroboration of their enamines. Hydroboration of aldehyde enamines by 9-borabicyclo[3.3.1]nonane (9-BBN), followed by methanolysis, affords the corresponding terminal alkenes in 75-90% yields. Unsaturated aldehyde enamines produce the corresponding dienes under these conditions. Enamines derived from substituted cyclic ketones and heterocyclic ketones are readily accommodated in this reaction to afford the corresponding alkenes in very good yields. The synthesis of pure (Z)- or (E)-alkenes is readily achieved from the same acyclic ketone enamine by modification of the hydroboration-elimination procedure: (A) hydroboration by 9-BBN followed by methanolysis or (B) hydroboration by borane methyl sulfide (BMS) followed by methanolysis and hydrogen peroxide oxidation. Mechanistic rationale is provided.
Pheromone 48. Eine neue synthese von (n,n+3)-alkadienen
作者:Hans Jürgen Bestmann、Reinhard Dötzer、Javier Manero-Alvarez
DOI:10.1016/s0040-4039(00)94907-4
日期:1985.1
Convenient conversion of aldehydes and ketones into the corresponding alkenes via hydroboration of their enamines. A remarkably simple synthesis of either (Z)- or (E)-alkenes
作者:Bakthan Singaram、Christian T. Goralski、Milind V. Rangaishenvi、Herbert C. Brown
DOI:10.1021/ja00183a068
日期:1989.1
Preparation of (Z)-alkenes, ketones, and alkynes via trialkyltin chloride induced intramolecular transfer reaction of lithium 1-alkynyltrialkylborates. Stereoselective synthesis of the sex pheromones of the Douglas fir tussock moth, the gypsy moth, and the wild silkmoth Antheraea polyphemus