15753-47-6Relevant academic research and scientific papers
N-(chloromethyloxycarbonyl)pyrrolidine as a source of the HOCH2- synthon
Guijarro, Albert,Yus, Miguel
, p. 5593 - 5596 (1996)
The reaction of N-(chloromethyloxycarbonyl)pyrrolidine (1) with lithium powder and a catalytic amount of DTBB (2.5 mol %) in the presence of different electrophiles [Me3SiCl, Bu(i)CHO, Bu(t)CHO, PhCHO, Et2CO, (CH2)5CO, PhCOMe, Ph2CO] in THF at -78°C leads, after hydrolysis with water, to the expected functionalised carbamates 2. Deprotection of the acetophenone derivative 2g with DIBALH at THF reflux yields, after hydrolysis, the corresponding 1,2-diol 3g.
SN2 Reactions at Tertiary Carbon Centers in Epoxides
Zhang, Yong-Qiang,Poppel, Christina,Panfilova, Anastasia,Bohle, Fabian,Grimme, Stefan,Gans?uer, Andreas
supporting information, p. 9719 - 9722 (2017/08/08)
Described herein is a novel concept for SN2 reactions at tertiary carbon centers in epoxides without activation of the leaving group. Quantum chemical calculations show why SN2 reactions at tertiary carbon centers are proceeding in these systems. The reaction allows flexible synthesis of 1,3-diol building blocks for natural product synthesis with excellent control of the relative and absolute configurations.
Selective transition-metal-free vicinal cis-dihydroxylation of saturated hydrocarbons
Bering, Luis,Antonchick, Andrey P.
, p. 452 - 457 (2016/12/30)
A transition-metal-free cis-dihydroxylation of saturated hydrocarbons under ambient reaction conditions has been developed. The described approach allows a direct and selective synthesis of vicinal diols. The new reaction thereby proceeds via radical iodination and a sequence of oxidation steps. A broad scope of one-pot dual C(sp3)-H bond functionalization for the selective synthesis of vicinal syn-diols was demonstrated.
Homogeneous and heterogeneous photoredoxcatalyzed hydroxymethylation of ketones and keto esters: Catalyst screening, chemoselectivity and dilution effects
Griesbeck, Axel G.,Reckenthaeler, Melissa
supporting information, p. 1143 - 1150 (2014/06/09)
The homogeneous titanium- and dye-catalyzed as well as the heterogeneous semiconductor particle-catalyzed photohydroxymethylation of ketones by methanol were investigated in order to evaluate the most active photocatalyst system. Dialkoxytitanium dichlorides are the most efficient species for chemoselective hydroxymethylation of acetophenone as well as other aromatic and aliphatic ketones. Pinacol coupling is the dominant process for semiconductor catalysis and ketone reduction dominates the Ti(OiPr)4/methanol or isopropanol systems. Application of dilution effects on the TiO2 catalysis leads to an increase in hydroxymethylation at the expense of the pinacol coupling.
Mild deprotection of methylene acetals in combination with trimethylsilyl triflate-2,2′-bipyridyl
Fujioka, Hiromichi,Senami, Kento,Kubo, Ozora,Yahata, Kenzo,Minamitsuji, Yutaka,Maegawa, Tomohiro
experimental part, p. 426 - 428 (2011/02/26)
The facile deprotection of methylene acetal protection of diols under mild conditions is established. The combination of trimethylsilyl triflate (TMSOTf) and 2,2′-bipyridyl followed by a weakly acidic hydrolysis was effective and the substrates having acid sensitive functional groups can be tolerated under the stated conditions. The selective deprotection between methylene acetal and benzophenone ketal was achieved.
Dispiro-1,2,4-trioxane analogues of a prototype dispiro-1,2,4-trioxolane: Mechanistic comparators for artemisinin in the context of reaction pathways with iron(II)
Tang, Yuanqing,Dong, Yuxiang,Wang, Xiaofang,Sriraghavan, Kamaraj,Wood, James K.,Vennerstrom, Jonathan L.
, p. 5103 - 5110 (2007/10/03)
Single electron reduction of the 1,2,4-trioxane heterocycle of artemisinin (1) forms primary and secondary carbon-centered radicals. The complex structure of 1 does not lend itself to a satisfactory dissection of the electronic and steric effects that influence the formation and subsequent reaction of these carbon-centered free radicals. To help demarcate these effects, we characterized the reactions of achiral dispiro-1,2,4-trioxolane 4 and dispiro-1,2,4-trioxanes 5-7 with ferrous bromide and 4-oxo-TEMPO. Our results suggest a small preference for attack of Fe(II) on the nonketal peroxide oxygen atom of 1. For 4, but not for 5 and 6, there was a strong preference for attack of Fe(II) on the less hindered peroxide bond oxygen atom. The steric hindrance afforded by a spiroadamantane in a five-membered trioxolane is evidently much greater than that for a corresponding six-membered trioxane. Unlike 1, 5-7 fragment by entropically favored β-scission pathways forming relatively stable α-oxa carbon-centered radicals. These data suggest that formation of either primary or secondary carbon-centered radicals is a necessary but insufficient criterion for antimalarial activity of 1 and synthetic peroxides.
2,3,5-TRISUBSTITUTED PYRIDINES AS INHIBITORS OF CYCLOOXYGENASE-2
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Page 31, (2010/02/07)
The invention encompasses the novel compound of Formula (I) as well as a method of treating cyclooxygenase-2 mediated diseases comprising administration to a patient in need of such treatment of a non-toxic therapeutically effective amount of a compound of Formula (I). The invention also encompasses certain pharmaceutical compositions for treatment of cyclooxygenase-2 mediated diseases comprising compounds of Formula (I).
Pyridyl group assisted deprotonation of a methyl group on silicon: Complex induced proximity effect and novel hydroxymethylation
Itami,Kamei,Mitsudo,Nokami,Yoshida
, p. 3970 - 3976 (2007/10/03)
A novel methodology for the deprotonation of a methyl group on silicon has been developed. This newly developed α-lithiation protocol is based on the intramolecular pyridyl group coordination to stabilize the α-silyl carbanion together with the inherent silicon α effect. It was found that the deprotonation (t-BuLi/Et2O/-78 °C) occurs with 2-pyridyltrimethylsilane but not with other related silanes such as phenyltrimethylsilane, 3-pyridyltrimethylsilane, and 4-pyridyltrimethylsilane. It seems that this deprotonation proceeded through the agency of the complex-induced proximity effect (CIPE) of a 2-pyridyl group on silicon. 1H NMR analysis of (2-pyridyldimethylsilyl)methyllithium revealed the intramolecular coordination of a pyridyl group to lithium. (2-Pyridyldimethylsilyl)-methyllithium was found to react with chlorosilanes, hydrosilanes, chlorostannanes, bromine, iodine, organic bromides, aldehydes, and ketones in good to excellent yields. The resultant adducts were further oxidized with H2O2/KF to give the corresponding alcohols in excellent yields. Thus, this two-step transformation provides an efficient method for the nucleophilic hydroxymethylation.
Efficient o-trimethylsilylation of alcohols and phenols with trimethylsilyl azide catalyzed by tetrabutylammonium bromide under neat conditions
Amantini,Fringuelli,Pizzo,Vaccaro
, p. 6734 - 6737 (2007/10/03)
A very efficient procedure for the trimethylsilylation of a wide variety of alcohols, including primary, allylic, benzylic, secondary, hindered secondary, tertiary, and phenols is reported. The reactions were carried out under neat conditions with trimethylsilyl azide (TMSN3) and, when necessary, in the presence of a catalytic amount (20 mol %) of tetrabutylammonium bromide (TBABr) at 30 or 70 °C. Under catalytic conditions, the yields of the corresponding trimethylsilyl ethers were greater than 91%. This procedure also allows the selective protection of primary and secondary alcohols in the presence of tertiary ones.
Tri-n-butyl[2-(trimethylsilyl)-ethoxymethoxymethyl]stannane: A convenient hydroxymethyl anion equivalent
Fernández-Megía, Eduardo,Ley, Steven V.
, p. 455 - 458 (2007/10/03)
Tri-n-butyl[2-(trimethylsilyl)-ethoxymethoxymethyl]stannane 3 was used as a protected precursor for a hydroxymethyl anion which was added to various carbonyl and carboxyl electrophiles.
