Iron-Promoted Elimination of β-Thioalkoxy Alcohols. Olefination by Coupling of a Carbonyl Group with a Dithioacetal
摘要:
Treatment of propargylic dithiolanes with (BuLi)-Bu-n followed by a carbonyl electrophile yields the corresponding propargylic dithioacetals. Upon treatment with 1 equiv of Fe(acac)(3) and excess MeMgI, elimination of SR and OH moieties from 8 affords the corresponding olefins in satisfactory yield. Benzylic dithioacetals behave similarly. The reaction can be considered an alternative of McMurry coupling of two different carbonyl equivalents.
Abstract Silicachloride (SiO2-Cl), as a heterogeneous reagent, has been used for the efficient dehydration of tertiary alcohols under mild reaction conditions. For comparison, we have also used trimethylsilyl chloride (TMSCl) as a homogeneous reagent for this purpose. We have found that silicachloride is a more efficient reagnet than trimethylsilyl chloride for this purpose. Handling of SiO2-Cl is
Hydroarylation of Alkenes Using Anilines in Hexafluoroisopropanol
作者:Ignacio Colomer
DOI:10.1021/acscatal.0c00872
日期:2020.6.5
one to modulate bioactive molecules. This work reports a method for the selective functionalization of anilines using hexafluoroisopropanol (HFIP) as a solvent to promote an acid-catalyzed hydroarylation of olefins. Mechanistic experiments revealed that HFIP both protonates the alkene and selectively enables anilines toward the electrophilic aromatic substitution. This powerful strategy has been applied
Regio- and stereoselective hydrostannation of allenes using dibutyliodotin hydride (Bu2SnIH) and successive coupling with aromatic halides
作者:Naoki Hayashi、Kazunao Kusano、Shingo Sekizawa、Ikuya Shibata、Makoto Yasuda、Akio Baba
DOI:10.1039/b712998j
日期:——
Regio- and stereoselective hydrostannation of allenes by using di-n-butyliodotin hydride (Bu2SnIH) was accomplished to give α,β-disubstituted vinyltins, which induced the synthesis of multi-substituted alkenes in a one-pot procedure.
Triphosgene and DMAP as Mild Reagents for Chemoselective Dehydration of Tertiary Alcohols
作者:Moshood O. Ganiu、Alexander H. Cleveland、Jarrod L. Paul、Rendy Kartika
DOI:10.1021/acs.orglett.9b01959
日期:2019.7.19
The utility of triphosgene and DMAP as mild reagents for chemoselective dehydration of tertiary alcohols is reported. Performed in dichloromethane at room temperature, this reaction is readily tolerated by a broad scope of substrates, yielding alkenes preferentially with the (E)-geometry. While formation of the Hofmann products is generally favored, a dramatic change in alkene selectivity toward the
作者:Jack E. Baldwin、Robert M. Adlington、Jeffery C. Bottaro、Jayant N. Kolhe、Ian M. Newington、Matthew W.D. Perry
DOI:10.1016/s0040-4020(01)87648-1
日期:1986.1
The lithium salts of trityl- and diphenyl-4-pyridylmethyl-hydrazones of both aldehydes and ketones react with electrophiles (alkyl halides, aldehydes, ketones, crotonates) at low temperature to form C-trapped azo compounds ; these Intermediates decompose homolytically with loss of nitrogen below room temperature and can be diverted in a synthetically useful way to alkanes, alkenes, alcohols or saturated