Unsaturated compounds, alkylation phosphorus

Schwartz (1972) also noted the detection of about 70 glycerol-l-alkyl ethers in milk fat. Saturated ethers, both odd and even from C-10 through C-18, were found, with traces of ethers up to C-25 present. Fifty-five unsaturated ethers were separated, but only the A-9, A-9, 12, and A-9, 12,15 compounds were tentatively identified. In addition, Schwartz isolated over 50 bound aldehydes probably derived from the glycerol-l-alkenyl ethers (phosphorus free). 

Peptidomimetics in which one amide bond is replaced by a phosphinic acid (R-P(0H)(=0)-R phosphinic peptides ) are of interest as potential protease inhibitors [17-19]. These compounds have been prepared either from orthogonally protected phosphorus-containing monomers [17,18,20], or by forming the phosphorus-containing fragments on solid phase, as sketched in Figure 11.4 [19,21], Phosphinic acids have been prepared on solid phase mainly by reaction of carbon electrophiles with monoalkylphosphinates. As carbon electrophiles, acrylates, aldehydes, reactive alkyl halides, or a, 3-unsaturated ketones can be used. 

The most familiar of the sulfonic adds derived from camphor is 10-camphorsulfonic add (44, Reychler s acid45). Both enantiomers are commercially available and convenient procedures exist for their preparation by sulfonation of camphor (ref 46 exemplifies the racemate, but the procedure works equally well for optically active camphor). The free acid is often applied to the resolution of basic compounds such as amines. A detailed review on the use of derivatives of this acid as auxiliaries has been given3. Esters of this add are normally obtained by the reaction of the alcohols with the sulfonyl chloride which is also commerdally available (or readily obtained by the reaction of the free acid with phosphorus pentachloride or thionyl chloride46,48). Such esters with unsaturated alcohols have been used for diastereoselective [1,2] sigma tropic rearrangements (Section D.1.6.3.3.). Allyl esters have been used for enantioselective alkylation reactions, in which camphorsulfonic acid reacts as the chiral leaving group (Section D.1.1.2.2.). 

The iV-propargylaminophosphines (78) readily rearrange to give the azabuta-dienylphosphine (79) via intramolecular nucleophilic attack of phosphorus at the terminal acetylenic carbon. Full details have now appeared of the reactions of 2 -1,2,3-diazaphosphole derivatives (80) with alkyl halides, giving 2,3-disub-stituted indoles as the major product. Several examples of the attack of phosphines at carbon of a, -unsaturated carbonyl compounds have been described. The betaine (81) is the active intermediate in the triphenylphosphine-induced polymerization of maleic anhydride. Phosphines also catalyse the... 

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