The phosphorus–oxygen bond formation reactions often observed for the sterically crowded triarylphosphines and their radical cations were studied by DFT calculation. oxidations of trimethyl-, triphenyl-, trimesityl-phosphines to corresponding phosphine oxides with peroxides are shown proceed through SN2 like transition states overall influence steric hindrance on activation energy is limited. r...

Secondary phosphine oxides R2P(O)H are a relatively stable tautomeric form of secondary phosphinous acids R2P–OH that with imine/iminium species, or their donors, compounds P(O)–Csp3–N linkage (the phospha-Mannich reaction). These can be referred to as (α-aminoalkyl)phosphine oxides, (α-phosphinoylalkyl)amines, P(O),N-acetals. Compared P–Csp3–N linkages P,N-acetals, products reactions involving...

In this review, we describe the papers and patents dealing with the fluorous biphasic system (FBS) hydrosilylation reactions reported to date. Despite the limited number of reports, the FBS hydrosilylation reaction has been extremely successful. In all cases fluorous monophosphines (either alkylic or perfluoroalkylsilyl-substituted derivatives of triphenylphosphine) have been employed as ligand...

Deals with a study of the mineralogical and organic components of the monthly dust-fall deposited over Al Ain city, some 150km east of Abu Dhabi and 130km southeast of Dubai. The identification of the mineralogical and organic composition was carried out by means of infrared spectroscopy. This study reveals that the principal constituents of dust-fall over the studied city are calcite, gypsum, ...

Two 5 modified 2'-deoxyuridin triphosphates and a 7 modified 2'-deoxy-7-deazaadenosine were synthesized carrying a terminal azide linked to the base. For probing the sterical influence on incorporation and Staudinger ligation different sized flexible linkers were chosen. All three nucleotides can completely replace their natural counterparts in primer extension as well as polymerase chain react...

Some phosphorus chemical shifts of quaternary phosphorium salts had previously been reported4 and it was shown that these chemical shifts could be linearly related to the sum of the ob values5 for the corresponding groups in tertiary phosphines. The op values are group contributions which have been scaled so that the methyl group has a value of zero, in analogy to H a m m e t and T a f t o-para...