Palladium(II)-Catalyzed Regio- and Stereoselective Hydroarylation of Diphenylphosphorylallenes with Arylboronic Acids in the Presence of Sodium Hydroxide and Oxygen
The palladium(II)‐catalyzed hydroarylation of diphenylphosphorylallenes (via 1,2‐addition of the allenic double bond) with arylboronicacids in the presence of sodium hydroxide and oxygen is developed. The regioselectivities turn out to be well controlled, affording 2‐aryl‐3‐(diphenylphosphinyl)alkenes as the only product. Moreover, the stereoselectivities for reactions of γ‐substituted allenes can
A cooperative CuBr2 and tert‐butyl hydroperoxide (TBHP) system allowed for the highly stereoselective dibromination and bromohydroxylation reactions of (diphenylphosphoryl)allenes under mild conditions.
Highly functionalised (γ-azido/γ-fluoro-β-iodo/)vinyl derivatives from phosphorus based allenes or allenoates: I⋯O halogen bonding interactions
作者:Mandala Anitha、K. C. Kumara Swamy
DOI:10.1039/c9ob00715f
日期:——
azidation/fluorination of phosphorus-based allenes or allenoates (allenyl esters) or a sulphur based allene. Surprisingly, the reaction of (γ,β)-diiodo-vinyl-phosphonate with TBAF [n-Bu4NF] led to the corresponding allenylphosphonate; in contrast, the use of CsF in a similar reaction led to novel γ-diiodo-allenylphosphonate along with the corresponding non-halogenated allenylphosphonate. The combination
通过碘化,随后磷基丙二烯或烯丙酸酯(烯丙酸酯)或硫基丙二烯的叠氮化/氟化来合成多功能γ-叠氮基/γ-氟-β-碘-乙烯基膦氧化物/膦酸酯/酯/砜。令人惊奇的是,(γ,β)-二碘-乙烯基膦酸酯与TBAF [ n- Bu 4 NF]的反应产生了相应的烯丙基膦酸酯。相反,在类似反应中使用CsF会导致产生新的γ-二碘代烯丙基膦酸酯以及相应的非卤代烯基膦酸酯。AgF 2的组合/ CuBr可用于获得γ-氟-β-碘-乙烯基膦氧化物和相关的无磷γ-氟-β-碘-乙烯基酯。在许多情况下,还观察到I⋯O卤素与氧的非共价键相互作用(“卤素键”),涉及磷酰基(PO)氧,如单晶X射线晶体学所证明的那样。
Base catalysed intermolecular cyclisation of N-protected o-amino benzaldehyde/acetophenone with phosphorus/sulphur based allenes: facile synthesis of substituted quinolines
作者:Mandala Anitha、G. Gangadhararao、K. C. Kumara Swamy
DOI:10.1039/c6ob00259e
日期:——
allenylphosphonates in the presence of a simple base leads to quaternary carbon substituted phosphono-quinolines which undergo thermalrearrangement to O-phosphorylated quinolines. The present one-pot reaction involves intermolecular cyclisation, dehydration, and benzoyl group rearrangement followed by a novel phosphoryl group migration. The migration was less facile/not observed in the reactions using allenylphosphine
Synthesis of chiral phosphorus compounds from readily available substrates by a facile method is an attractive strategy. In this study, an efficient route for copper-catalyzedasymmetric boroprotonation of phosphinylallenes with bis(pinacolato)diboron with high regioselectivity was developed, affording chiral allylphosphine oxides in high yields with high enantioselectivities of up to 98% ee. The synthetic
通过简便的方法从容易获得的底物合成手性磷化合物是一种有吸引力的策略。在这项研究中,开发了一种铜催化的膦基丙二烯与双(频哪醇)二硼的高区域选择性不对称硼质子化的有效途径,以高产率和高达 98% ee 的高对映选择性提供手性烯丙基氧化膦。通过将手性烯丙基氧化膦轻松转化为几种立体特异性产物,进一步证明了合成效用。