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Phosphorus nucleophiles reviews

Half this review is concerned with aziridination, but other cycloadditions are generally excluded, being reviewed elsewhere in this series (Volume 4, Part 4 and Volume 5, Part 4). The second half of this review covers additions of nitrogen and a chalcogen or halogen, or a second nitrogen. No examples of addition of N + P were found this transformation can be achieved indirectly by opening aziridines with phosphorus nucleophiles. ... [Pg.470]

No reactions of oxa- or thiadiazines with carbon or phosphorus nucleophiles or with electrophiles at nitrogen were reported during the time period of this review. [Pg.474]

A review has been published on the work of Vasella s group on asymmetric induction in 1,3-dipolar cycloadditions of, and the addition of phosphorus nucleophiles to, N-glycosyl-nitrones, with the purpose of providing a general synthesis of a-aminophosphonic... [Pg.111]

Recent developments in metal-catalysed asymmetric addition of phosphorus nucleophiles, with the formation of P-C bonds, have been reviewed the metals and electrophiles have been discussed widely. DFT study of salicylaldehyde-Al(ni)-catalysed hydrophosphonylation of benzaldehyde by diethylphosphonate (DEPH) reveals that P-H activation by the formation of Al-phosphite species is followed by rate-determining C-P bond formation, which determines the predominant (S) configuration (with 99% ee) of the a-hydroxyl phosphonate ester on regeneration of the salicylaldehyde-Al(III) complexes. Reduction of activated carbonyl groups by alkylphosphanes can proceed either through path a or path b (Scheme 35), as evidenced experimentally and theoretically. ... [Pg.31]

A review <94Ml 422-01) on 1,3-heterophospholes (Chapter 3.16) compares their reactivity to that of di- and triazaphospholes which are covered in this chapter. In contrast to 1,3-azaphospholes the latter contains two-coordinate nitrogen atoms in the ring. The RC/N exchange lowers the charge density at the phosphorus atom and facilitates the attack by hard nucleophiles. [Pg.775]

The most interesting properties of phosphoranes, i.e. their role as intermediates or transition states of nucleophilic addition reactions of four-coordinate phosphorus compounds and their intramolecular rearrangements according to BPR or TR, have already been fully considered. The synthetic potential of stable phosphoranes has been reviewed by Burger in great detail (B-79MI11702), and only some special aspects need be mentioned in this chapter. [Pg.535]

This section emphasizes work done in the last few years. The reader is referred to other sources for reviews of older work236 or more general discussions of nucleophilic reactions at phosphorus.237"245 More general discussions of enzymic phosphoryl and nucleotidyl transfer are available,246 248 and the role of divalent metal ions has been reviewed.249"251... [Pg.443]

The synthetic utility of a-phosphorus- and a-thio-stabilized carbanions is the subject of numerous reviews.21 Notable are additions of phosphonium ylides (237),183 sulfonium ylides (238),l84 ° oxosulfo-nium ylides (239)184 " and sulfoximine ylides (240)184,1 to electron-deficient alkenes which afford nucleophilic cyclopropanation products. In contrast, with a-(phenylthio)-stabilized carbanions, which are not acyl anion equivalents, either nucleophilic cyclopropanation or retention of the hetero substituent occurs, depending on the acceptor and reaction conditions used. For example, carbanion (241) adds to 1,1-... [Pg.115]

A review (91 references) on electrophilic and nucleophilic reactions of trivalent phosphorus acid derivatives, reactions of two-coordinate phosphorus compounds, and miscellaneous reactions has appeared.228 Earlier in this review we looked at the heavy-atom isotope effects on reactions of Co(III)-bound /vnitrophenyl phosphate,186 the uranyl ion hydrolysis of /vnitrophcnyl phosphodiesters (218)-(220),190 and the Th(IV) hydrolysis of these.191... [Pg.76]

Aminolysis of phenyl dithioacetates,8 pyridinolysis of O-ethyl dithiocarbonates,9 reaction of pyrrolidine with O-ethyl 5-aryl dithiocarbonates,10 aminolysis of chlorothionformates,11 pyridinolysis of alkyl aryl thioncarbonates,12 reaction of anionic nucleophiles with nitrophenyl benzoate and its sulfur analogues,36 hydrolysis of methyl benzoate and phenyl acetate containing SMe, SOMe and S02Me substituents,42 solvolysis of phenyl chlorothioformate,79 synthesis of new thiadiazoles,124 examination of a neighbouring sulfonium group in ester hydrolysis,136 hydrolysis of V-type nerve agents,250 and the reactions of peroxymonosulfate ion with phosphorus(V) esters have all been looked at previously in this review. [Pg.88]

This chapter covers the main synthetically useful phosphonylation reactions, the corresponding processes of phosphinylation and tertiary phosphine oxide formation along with some related reactions. In all these reactions the phosphorus reactant (a phosphite, phosphonite, phosphinite, or derivative or tautomer thereof) is the nucleophilic component, herein these reactants are referred to collectively as phosphorus(III) reactants/acids, as appropriate in general these reagents are best used freshly distilled. Syntheses of phosphonates, phosphinates and tertiary phosphine oxides by nucleophilic substitution at phosphorus is not covered (for reviews of this area see Refs 6 and 16). [Pg.172]


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See also in sourсe #XX -- [ Pg.334 ]




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Phosphorus nucleophiles

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