Allyl diethyl phosphates

The palladium-catalyzed carbonylation reaction of allyl diethyl phosphate, in the presence of imines, gives either cis- or rraws-3-vinyl-/J-lactams, in high yields and in a stereoselective fashion (equation 160)574,575. The reaction is a [2 + 2] cycloaddition process which occurs under simple and mild conditions and has significantly more potential than the reaction of imines with ketenes (due to the more forcing conditions that are usually required to form the ketene intermediates). This reaction, however, only proceeds in low yield if the allyl phosphate is replaced with allyl acetate576. 

Alkylation and animation ofallylie phosphates.6 Allyl diethyl phosphates undergo efficient allylie alkylation and animation in the presence of this Pd(0) catalyst. Examples ... 

To expand the range of phosphates for preparation of organomanganese phosphates, alkyl-, phenyl-, and allyl diethyl-phosphates were attempted. Unfortunately, the oxidative addition of active manganese (Mn ) to these phosphates and the subsequent coupling reactions with electrophiles foiled to give the corresponding cross-coupled products. 

In another example, Pd2(dba)3 was used in conjunction with allyl diethyl phosphate, an unusual stoichiometric hydrogen acceptor in the oxidation of simple alcohols. Oxidative addition of Pd(0) into the allylic phosphate (generating a r-allyl-Pd(II) complex), is followed by an alcohol/phosphate displacement and subsequent /3-hydride elimination giving the oxidized alcohol... 

Both primary and secondary alcohols can be converted into the corresponding aldehyde or ketone by a method using allyl diethyl phosphate, as hydrogen acceptor, in combination with either potassium or sodium carbonate and Pd(OAc)2 as catalyst. For example, 2-octanone and cirmamaldehyde have each been synthesized by this route, and in yields of 85 and 90%, respectively. ... 

In a rare example of the use of phenylselenides as radical precursors in the generation of alkene radical cations by the fragmentation approach, Giese and coworkers generated a thymidine C3/,C4/ radical cation by expulsion of diethyl phosphate. Trapping experiments were conducted with methanol and with allyl alcohol (Scheme 16), when nucleophilic attack was followed by radical cyclization [66]. 

The reaction of but-l-en-3-yl diethyl phosphate with diethylamine produces N,N-diethylpent-3-enamide (86%), indicating that a Ji-allyl complex is involved in the carbonylation reaction. No isomerism to the a,p-unsaturated amides was observed. 

A regio-, diastereo- and enantioselective synthesis of amino acids was reported by Takemoto and coworkers. The glycine equivalent ethyl diphenylimino glycinate was used as pronucleophile (Scheme 9.14), while the Hgand was a bidentate chiral phosphite, and 3-arylaUyl diethyl phosphates were employed as allylic substrates [39, 46]. 

The Ir-catalyzed enantioselective allylic substitution reaction can be used for the synthesis of -substituted a-amino acids . For example, the enantioselective Ir-catalyzed allylic substitution of 3-arylallyl diethyl phosphates 5.24 with pronucleophile diphenylimino gly-cinate 5.25 is achieved up to 98% ee by using bidentate chiral phosphite ligand 5.26. By changing the base, both diastereoisomeric substitution products 5.27a and 5.27b could be formed selectively. 

A highly regio-, diastereo-, and enantioselective desymmetrisation of five-, six-, and seven-membered meso-cyclic allylic bis-diethyl phosphates (104), (105) and (106), was achieved with diethylzinc using catalytic amounts of [Cu(OTf)]2, CgHg and phosphoramidite ligands (107). The addition of diethylzinc to cyclopentene, cyclohexene, and cycloheptene bis-diethyl phosphates, provided allylic monophosphates (108), (109) and (110) with enantiomeric excess of up to 87, 94 and >98%, respectively (Scheme 28). ... 

Cation and solvent hydrogen bonding to the hydrophilic phosphate group of the anion BNPPA (l,l-binaphthyl-2-diyl phosphate) (71) leads to bilayers with an interior hydrophilic region and with hydrophobic binaphthyl groups on both exterior sides.A simple thiophosphate-based method for 2-alkylidenation of lactones has been described. Phosphorus-derived chiral auxiliaries for a-alkylation of secondary amines by anodic oxidation has been elaborated. lodotrimethyl-sUane, which is routinely used for the dealkylation of ethers and esters, may be used to iodinate allyl or benzyl diethyl phosphates. ... 

Ravn MM, Jin Q, Coates RM. Synthesis of allylic isoprenoid diphosphates by Sfj2 displacement of diethyl phosphate. Eur. J. Org. Chem. 2000 1401-1410. 

Allylic phosphates are used for carbonylation in the presence of amines under pressure. Carbonylation of diethyl neryl phosphate (389) affords ethyl homonerate (390), maintaining the geometric integrity of the double bond[244]. The carbonylation of allyl phosphate in the presence of the imine 392 affords the /3-lactam 393. The reaction may be explained by the formation of the ketene 391 from the acyl phosphate, and its stereoselective (2 + 2] cycloaddition to the imine 392 to give the /3-lactam 393(247],... 

Diethyl[dimethyl(phenyl)sUyl aluminum. ( HjlCHOiSiAUC H,), (1). The aluminum reagent is prepared in situ by addition of (C HO AICl to QHdCHdiSiLi in THF at 0°. The reagent converts allylic phosphates into allylsilanes. Rearrangement products can be formed from unsymmetrical allylic phosphatc>... 

Diethyl phosphorocyanidate adds to a,/J-unsaturated aldehydes or ketones in the presence of lithium cyanide in a 1,2-fashion28. Boron trifluoride-diethyl ether complex catalyzed rearrangement of these allylic phosphates shows high E selectivity (>85 15) for the adducts derived from aldehydes and Z selectivity (>90 10) for ketone adducts. The selectivity of the rearrangement can be explained by assuming a chairlike transition state, in which the sterically more demanding x-substituent occupies the quasi-equatorial position. The steric requirement decreases in the order of R1 > CN > H. Thus, the cyano substituent occupies the quasi-equatorial position in the aldehyde-derived adduct (R1 = H), but the quasi-axial position in the ketone-derived adduct (R1 = CH3, C6H5). 

Allyl phosphorodichloridite. 1169 Bis(trimethyIsilyl) phosphonite, 2611 0-0-tert-Butyl diphenyl monoperoxophosphate, 3712 0-0-tert-Butyl di(4-tolyl) monoperoxophosphate, 3763 Diallyl phosphite (Di-2-propenyl phosphonite), 2456 Dibenzyl phosphite, 3658 Dibenzyl phosphorochloridate, 3650 Di(( -( -teri-butyl) ethyl diperoxophosphate, 3374 Dibutyl hydrogen phosphite, 3086 Diethyl ethanephosphonite, 2572 Diethyl 4-nitrophenyl phosphate, 3329 Diethyl 4-nitrophenyl thionophosphate, 3328 Diethyl phosphite, 1733... 

In a glove box, CuOAc (6.1 mg, 0.05 mmol) was placed in another vial. K-0-/-Bu (1 M in THF, 0.5 mL, 0.5 mmol) was added to the alkylborane at 25 °C, prepared in advance, and the mixture was stirred at 25 °C for 5 min to produce the corresponding alkylborate. Next, the alkylborate was then transferred to the vial containing the Cu salt. Finally, the allylic phosphate (0.5 mmol) was added. After stirring at 60 for 8 h, DCM was added to the mixture, which was then Altered through a short plug of silica gel, which was washed with diethyl ether. After the solvent was removed under reduced pressure, flash chromatography on silica gel (hexane) provided the desired product. ... 

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