814-16-4Relevant academic research and scientific papers
Iridium(III)-Catalyzed C-H Functionalization of Triarylphosphine Oxides with Diazo Dicarbonyl Compounds: Synthesis of α-Aryl 1,3-Dicarbonyl Derivatives
Lou, Qin-Xin,Li, Jing-Yu,Yang, Shang-Dong
supporting information, (2021/04/15)
A novel (pentamethylcyclopenta-1,3-dienyl)iridium(III)-catalyzed direct C-H functionalization of triarylphosphine oxides with diazo dicarbonyl compounds through carbene insertion has been developed. This strategy provides a simple and efficient route to t
Mukaiyama reagent-promoted metal-free preparation of alkynyl sulfones and phosphonates under mild conditions
Qi, Danyang,Dong, Wanrong,Peng, Zhihong,Zhang, Yingjun,An
, (2019/08/01)
An efficient and mild route for the formation sulfur or phosphor-substituted alkynes was herein demonstrated. The Mukaiyama reagent-mediated transformation started from easily-accessible substrates without carbon-carbon triple bonds, and the reaction proceeded under mild conditions (room temperature) in a one-pot manner, requiring for no transition metal-catalysts. The practical protocol featured for good functional groups tolerance (up to 41 examples) and high efficiency (up to 91% yields) towards alkynyl sulfones and alkynyl phosphonates at low cost.
Silver-Catalyzed Oxidative C(sp3)?P Bond Formation through C?C and P?H Bond Cleavage
Li, Lili,Huang, Wenbin,Chen, Lijin,Dong, Jiaxing,Ma, Xuebing,Peng, Yungui
supporting information, p. 10539 - 10544 (2017/08/22)
The silver-catalyzed oxidative C(sp3)?H/P?H cross-coupling of 1,3-dicarbonyl compounds with H-phosphonates, followed by a chemo- and regioselective C(sp3)?C(CO) bond-cleavage step, provided heavily functionalized β-ketophosphonates. This novel method based on a readily available reaction system exhibits wide scope, high functional-group tolerance, and exclusive selectivity.
Base-induced one-pot preparation of N- or P-substituted alkynes
Zhang, Yang,Zhang, Yanqin,Xiao, Jing,Peng, Zhihong,Dong, Wanrong,An, Delie
supporting information, p. 7806 - 7815 (2015/12/31)
An efficient method for the formation of C(sp)-N or C(sp)-P bonds is described. The facile transformation proceeds under mild conditions (0 or -20 °C) in a one-pot manner, and does not require transition-metal catalysts. The base-induced protocol exhibits good functional group tolerance (up to 44 examples) and high efficiency (up to 94 % yield) towards rare heteroatom-substituted acetylenes (N or P). Furthermore, the proposed mechanism was supported by the isolation of a key intermediate. An efficient method for the formation of C(sp)-N or C(sp)-P bonds is described. The facile transformation proceeds in the absence of any transition-metal catalysts under mild conditions (0 or -20 °C) in a one-pot manner with good functional group compatibility and with high efficiency.
Dynamic kinetic resolution of α-chloro β-keto esters and phosphonates: Hemisynthesis of Taxotere through Ru-DIFLUORPHOS asymmetric hydrogenation
Prevost, Sebastien,Gauthier, Sebastien,De Andrade, Maria Cristina Cano,Mordant, Celine,Touati, Ali Rhida,Lesot, Philippe,Savignac, Philippe,Ayad, Tahar,Phansavath, Phannarath,Ratovelomanana-Vidal, Virginie,Genet, Jean-Pierre
experimental part, p. 1436 - 1446 (2010/11/03)
The dynamic kinetic resolution (DKR) of racemic α-chloro β-ketoesters and α-chloro β-ketophosphonates through ruthenium-mediated asymmetric hydrogenation is reported. The corresponding α-chloro β-hydroxyesters and α-chloro β- hydroxyphosphonates were obtained in good to high enantio- and diastereomeric excesses using, in particular, the atropisomeric ligand DIFLUORPHOS. This methodology allowed an efficient preparation of the anti phenylisoserine side chain of Taxotere which has been used for the hemisynthesis of the cancer therapeutic agent itself. In addition, 13C NMR in chiral oriented solvents was used to investigate the DKR effect.
Novel cobalt(0)- or magnesium-mediated approaches to β-ketophosphonates
Orsini, Fulvia,Di Teodoro, Emanuela,Ferrari, Marinella
, p. 1683 - 1688 (2007/10/03)
Two novel approaches to β-ketophosphonates, based on cobalt(0)- or magnesium-mediated reactions of α-halophosphonates with esters are described.
Effect of allylic CH3-nFn groups (n = 1-3) on π-facial diastereoselection
Yamazaki, Takashi,Ichige, Tatsuro,Takei, Satoshi,Kawashita, Seiji,Kitazume, Tomoya,Kubota, Toshio
, p. 2915 - 2918 (2007/10/03)
(equation presented) Michael addition of various enolates toward γ-CH3-nFn-α,β-unsaturated ketones (n = 1-3) was proven to smoothly furnish the 1,4-adducts with high si face selectivities which monotonously decreased by reduction in the number of fluorines. Although the Felkin-Anh model correctly anticipates the present stereochemical outcome only with E-acceptors, the hyperconjugative stabilization of transition states by electron donation from the allylic substituents (the Cieplak rule) successfully explains the π-facial preference of both acceptors at least in a qualitative level.
TIN(II) CHLORIDE CATALYZED ADDITION OF DIAZO SULFONES, DIAZO PHOSPHINE OXIDES, AND DIAZO PHOSPHONATES TO ALDEHYDES.
Holmquist, Christopher R.,Roskamp, Eric J.
, p. 1131 - 1134 (2007/10/02)
Diazo sulfones, diazo phosphine oxides, and diazo phosphonates add to aldehydes in the presence of a catalytic amounts of tin(II) chloride to yield β-keto sulfones, β-keto phosphine oxides, and β-keto phosphonates, respectively.Reactions with primary aldehydes proceed in higher yields, 53-79percent, than those of secondary aldehydes, 42-56percent.Reactions with tertiary aldehydes, which are more sterically encumbered substrates, give only 5-36percent yields. KEY WORDS: Tin(II) chloride, catalyst, β-keto sulfones, β-keto phosphine oxides, and β-keto phosphonates.
Reaction of Diethyl Phosphorochloridite with Enolates: A General Method for Synthesis of β-Keto Phosphonates and α-Phosphono Esters through C-P Bond Formation
Lee, Koo,Wiemer, David F.
, p. 5556 - 5560 (2007/10/02)
The reaction of ketone enolates with diethyl phosphorochloridite, followed by air oxidation of the intermediate reaction products, has proven to be a general and convenient method for preparation of β-keto phosphonates.Fourteen β-keto phosphonates have been prepared by this method, in an average yield greater than 60percent.This procedure also appears to be applicable to preparation of both α-phosphono aldehydes and α-phosphono esters.Although special precautions may be necessary to avoid aldol condensation during formation of aldehyde enolates, in two cases it was shown that the resulting enolates react readily with diethyl chlorophosphite.Finally, a set of five ethyl esters was converted to α-phosphono esters by this method.Yields of the α-phosphono esters are influenced by steric hindrance at the enolate carbon, but the average yield for this series was ca. 70percent.Because this synthetic method relies upon an electrophilic phosphorus reagent for formation of the C-P bond, it is complementary to the traditional Arbuzov synthesis.On the basis of the 21 examples presented here, it appears to be more widely applicable.
A New Synthesis of β-Keto Phosphonates and β-Keto Silanes
Sampson, Paul,Hammond, Gerald B.,Wiemer, David F.
, p. 4342 - 4347 (2007/10/02)
A new preparation of β-keto phosphonates from α-bromo ketones, by reaction of dialkyl chlorophosphate electrophiles with the dilithiated derivative of the bromo ketone, is described.This umpolung approach is complementary to the classical Arbuzov synthesis in two important ways.It extends the range of possible ketone substrates, allowing use of secondary α-halo ketones or α-bromo ketones where the Arbuzov reaction often fails.It also extends the variety of phosphonates available, by allowing, for example, the direct preparation of bis-(trifluoroethyl)phosphonates.These fluoroalkyl phosphonates are not readily available via the Arbuzov reaction,because tris(trifluoroethyl) phosphite is only weakly nucleophilic.From our efforts to employ (trialkylsiloxy)vinyl bromides and n-butyllithium to generate an intermediate vinyllithium reagent, in place of forming the lithium enolate and using tert-butyllithium, a facile migration of trialkylsilyl groups from oxygen to the α-carbon has been discovered.This has been exploited in the development of a new route from α-bromo ketones to α-trialkylsilyl ketones.
