Phosphorus-carbon bonds reactions with

Carbon-phosphorus bonds are formed by the allylation of various phosphorus compounds. The allyldiphenylphosphine sulfide 346 is formed by the reaction of allylic acetates with lithium diphenylthiophosphide 343[215]. 

The Arbusov reaction is one of the best known methods for creating a carbon-phosphorus bond. In its simplest form (Michaelis-Arbusov) an alkyl halide reacts with a trialkyl phosphite to an alkanephosphonic acid diester as shown in Eq. (29) ... 

In this chapter, we first review the nature of the several forms of elemental phosphorus and then proceed to consider their uses for specific types of syntheses of compounds containing the carbon-phosphorus bond. Prior reviews have also been concerned with these topics.1 2 Our purpose here is to update these presentations and provide fundamentals for the practicing chemist venturing into the use of elemental phosphorus. We limit this discussion to the more-or-less direct syntheses of organophosphorus compounds from elemental phosphorus. We will consider reactions that generate monophosphorus species without C-P bonds as critical intermediates, pro-... 

Intramolecular alkyl transfer is a fundamental problem with this reaction this problem can be addressed with modification in structure of the reagents. Neutral trivalent phosphorus reagents do react with carbonyl compounds at much lower temperatures, but lead to several types of pentacoordinated phosphorus products.190-198 More will be noted about the use of such pentacoordinated phosphorus species for carbon-phosphorus bond formation in Chapter 5. 

We begin, however, with a brief consideration of a group of phosphorus compounds of significance for their utility in the formation of carbon-phosphorus bonds via reaction with organometallic reagents in displacement reactions. 

Lithium salts of resonance-stabilized organic anions have also found a role in carbon-phosphorus bond formation by displacement at phosphorus. The generation of the lithium salt derived from acetonitrile (or other aliphatic nitriles by reaction with butyl lithium or lithium diisopropylamide) provides for carbon-phosphorus bond formation by displacement of halide from phosphorus (Equation 4.24).68... 

The lithium salt of a substituted cyclopentadienyl anion has been used in reaction with phosphorus trichloride for carbon-phosphorus bond formation.70 The resultant simple displacement product ultimately undergoes dimerization and loss of four (from the dimer) equivalents of HC1 (Equation 4.25). 

A palladium-assisted reaction has also been used in the preparation of vinylic carbon-phosphorus bonds by addition to terminal alkynes.81 This reaction (Figure 6.20) provides vinylicphosphonates in good yield with reasonable regioselectivity (9 1) favoring addition at the internal position of the terminal alkyne. 

Sugars containing a carbon-phosphorus bond have been prepared by application of the Michaelis-Arbuzov reaction to bromodeoxy sugars. Thus, the reaction of 5-bromo-5-deoxy-l,2-0-isopropylidene-3-O-methyl-a-D-xylofuranose (131) with triethyl phosphite yields the corresponding diethyl phosphonate (132) compound 132 was employed for the synthesis of a sugar derivative having phosphorus as... 

The oxazoliumcarboxylic acid (147) is easily decarboxylated via the ylide (148) the neutral compound (149) is much more stable due to the low equilibrium concentration of the zwitterionic tautomer (150 Scheme 7). Oxazolium salts lacking substituents at the 2-position react with dialkyl acylphosphonates in the presence of triethylamine to give mixtures of l,4-oxazin-3-ones and 2-azetidinones the reaction (see Scheme 8) proceeds by electrophilic attack of the phosphonate on an oxazolium ylide, e.g. (151), followed by insertion of oxygen into the carbon-phosphorus bond, ring-opening, and formation of the enolate anion (152) which can cyclize in two alternative ways with expulsion of the phosphonate group. 

Reactions with Cleavage of One Carbon-Phosphorus Bond... 

Reactions with Cleavage of Two Carbon-Phosphorus Bonds... 

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