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Hot alkyne! The in situ generation of Ethynyl-1,2-BenziodoXol-3(1H)-one (EBX) from the corresponding silyl protected reagent using TBAF is reported. EBX displayed exceptional acetylene transfer ability to stabilized enolates, even at –78 °C. The mild react ...
The ion pair of the stereolabile C3-symmetric, i+o proton complex [1⋅H]+ of diaza-macropentacycle 1 and the configurationally stable Δ-TRISPHAT ([Δ-3]−) anion exists in the form of two diastereomers, namely, [Δ-(1⋅H)][Δ-3] and [Λ-(1⋅H)][Δ-3], the ratio of ...
We have investigated Five different poly(ethylene glycol) (PEG, 5 kDa) catechol derivatives in terms of their spontaneous surface assembly from aqueous solution, adlayer stability, and resistance to nonspecific blood serum adsorption as a function of the t ...
To gain insight into the biol. properties of tetramic acid lactam cylindramide 1, the analogs 4a-d bearing a cyclopentane ring instead of the pentalene unit were prepd. by tandem conjugate addn./enolate trapping of cyclopentenone 10; a Sonogashira or Still ...
A solvent-dependent silyl migration of lithiated biphenyls is described, involving the intermediate formation of a pentacoordinated silicate complex. Differences in the relative basicities of the aryllithium intermediates are the possible driving force for ...
H2S adsorption and dissociation on the gallium-rich GaAs( 001)- 4 x 2 surface is investigated using hybrid density functional theory. Starting from chemisorbed H2S on the GaAs( 001)- 4 x 2 surface, two possible reaction routes have been proposed. We find t ...
NH3 adsorption and dissociation on gallium-rich GaAs(0 0 1)-4 x 2 surface have been investigated using hybrid density functional theory. NH3 is found to adsorb molecularly onto GaAs(0 0 1)-4 x 2 via formation of a dative bond with an adsorption energy of 2 ...
This paper reports the allylic bromide rearrangement of 3-bromo-3-alkenyl-azetidin-2-ones, induced by m-chloroperbenzoic acid, N-bromosuccinimide or benzoylperoxide as radical initiators. The substitution of bromide by resin supported acids, followed by hy ...
The protonation of diphosphinoamines attached to pyridine at the ortho-position quantitatively affords the corresponding iminobiphosphine isomers. The starting material can be recovered quantitatively by deprotonation with base. The system represents a new ...
Efficient methods for the stereoselective synthesis of polyfunctional (E)- and (2)-alkenes and conjugated (EE)- and (E,2)-dienones are presented. They rely upon one-pot, four-component processes that condense 1-oxy-1,3-dienes, silyl enol ethers, SO2, and c ...
