The reaction of sodium diselenide with opticallyactive alkyl tosylates or chlorides is found to be a useful method for the synthesis of opticallyactive dialkyl diselenides. Opticallyactive monoterpene diselenides derived from menthane, carane, pinane, and bornane systems have been obtained. The influence of the terpene fragment of the obtained diselenides on the diastereomeric excess of the methoxyselenylation
been obtained by the straightforward reaction of 1,1′-dilithioferrocene-TMEDA adduct with either (+)-dineomenthyl diselenide or (−)-bis(cis-myrtanyl) diselenide. We also report herein on the X-ray crystalstructure of known 1,1′-bis(phenylseleno)ferrocene, Fe(C5H4SePh)2. All newly-obtained derivatives were characterized by 1H and 13C NMR, mass spectra and elemental analyses.
我们报道了通式为:Fe(C 5 H 4 SeR *)(C 5 H 5)和Fe(C 5 H 4 SeR *)2的手性二茂铁硒化物的合成,其中R * =新薄荷基和顺式-扁桃基。通过1,1'-二硫代二茂铁-TMEDA加合物与(+)-二烯薄荷基二硒化物或(-)-双(顺式-扁桃基)二硒化物的直接反应获得标题化合物。我们还报告了已知的1,1'-双(苯基硒代)二茂铁Fe(C 5 H 4 SePh)2的X射线晶体结构。所有新获得的衍生物的特征是1 H和13 C NMR,质谱和元素分析。
Synthesis and reactions of the optically active selenols derived from monoterpenes
the synthesis of opticallyactive selenols, derived from p-menthane, carane, and pinane, is described. The selenols were oxidized with air to give the opticallyactive diselenides, and were also converted into the corresponding allylic selenides via reaction with Z- and E-cinnamyl, geranyl, and neryl chlorides. Oxidation of the allylic selenides with mCPBA gave the opticallyactive alcohols via [2,3]-sigmatropic
Regiospecific transformation of 3-hydroxy-2-substituted-2,3-dihydroisoindol-1-ones into their aryl and alkyl 7-selenium derivatives, via metallation and subsequent reaction with diselenides, is described.
Asymmetric selenocyclization with the use of dialkyl monoterpene diselenides
Selenocyclization with the use of the monoterpene diselenides from menthane, carane and pinane groups has been studied. The conditions for asymmetric selenocyclization have been optimized. It has been established that the best enantiomeric excesses were obtained in the case of selenocyclization for the unsubstituted alkyl diselenides with (+)-dineomenthyl diselenide. The results of the selenocyclization of the (+)-dineomenthyl diselenide with the unsaturated alcohols and acids are presented. (C) 2007 Elsevier Ltd. All rights reserved.