Iron-Catalyzed Diastereoselective Synthesis of Unnatural Chiral Amino Acid Derivatives
作者:Hao Zhang、Haifang Li、Haijun Yang、Hua Fu
DOI:10.1021/acs.orglett.6b01493
日期:2016.7.15
An iron-catalyzed diastereoselectivesynthesis of unnatural chiral (S)-α-amino acids with γ-quaternary carbon centers has been developed. The protocol uses inexpensive iron salt as the catalyst, readily available 2-phthaloyl acrylamide and alkenes as the starting materials, and phenylsilane as the reductant, and the reactions were performed well in mixed solvent of 1,2-dichloroethane and ethylene glycol
Iron-Catalyzed Alkenylation of Grignard Reagents by Enol Phosphates
作者:Gérard Cahiez、Olivier Gager、Vanessa Habiak
DOI:10.1055/s-2008-1067194
日期:2008.8
Stereoselective preparation of trisubstituted olefins can be easily performed from an Z/E-mixture of enol phosphates by reacting only the E-isomer with a Grignardreagent in the presence of Fe(acac) 3 . This procedure combines a kinetic differentiation and a stereoselective reaction. The coupling is very chemoselective in the presence of an alkyl chloride, an ester, a ketone or a nitrile.
Iodine induced transformations of alcohols under solvent-free conditions
作者:Gaj Stavber、Marko Zupan、Stojan Stavber
DOI:10.1016/j.tetlet.2006.09.154
日期:2006.11
Iodine has been shown to be an efficient catalyst for transformations of alcohols under solvent-free conditions. In the presence of 5% of iodine, tertiary alcohols underwent dehydration forming the corresponding alkenes, while in the case of 2-phenylpropane-2-ol cyclodimerisation to 1,1,3-trimethyl-3-phenylindane took place. Secondary and primary benzyl alcohols under the same conditions gave the corresponding ethers. (c) 2006 Elsevier Ltd. All rights reserved.
Dehydration of Alcohols in Dimethyl Sulfoxide<sup>1,2</sup>
作者:Vincent J. Traynelis、William L. Hergenrother、Joel R. Livingston、John A. Valicenti
DOI:10.1021/jo01054a022
日期:1962.7
The Treatment of Facial Verrucae With the Pulsed Dye Laser
作者:Hannah Vargas、Christopher R. Hove、Marsha L. Dupree、Edwin F. Williams
DOI:10.1097/00005537-200209000-00007
日期:2002.9
AbstractObjectives/Hypothesis To evaluate the treatment of facial verrucae with the pulsed dye laser.Study Design A prospective, nonrandomized, nonblinded pilot study evaluating the treatment of facial verrucae with the pulsed dye laser.Methods Twelve patients with facial verrucae (four recalcitrant) were identified and followed in the study in the setting of a tertiary referral center. The treatment consisted of the flash‐lamp pumped pulsed dye laser (585 mn) with a spot size of 5 mm at fluences between 9.0 and 13 J/cm2. Each lesion received one or two pulses with 2 mm of surrounding normal skin included in the treatment. One patient had paring prior to pulse treatment. The patients were examined 3 to 4 weeks after each procedure, and clinical assessment of the lesion was documented.Results Patient ages ranged from 18 to 47 years. Four patients had refractory lesions, and eight patients had never undergone previous treatment. All 12 patients had full resolution of their facial warts after one to three treatment sessions. No complications such as scarring, alopecia, or recurrence were encountered. Follow‐up ranged from 10 to 33 months.Conclusions Pulsed dye laser therapy is highly effective and safe therapy for facial verrucae. This method appears to selectively destroy warts without damaging surrounding skin.