Phillips Esters

Phillips Chemical Company, See Chevron Phillips Chemical Company LP, 243 Phillips Petroleum Company, 243 Phorate, 105 PHORIL , phorate, 105 PHOSFLEX , phosphorus esters, 105 Phosgene, 105... 

R. P. Iyer, J. H. Boal, L. R. Phillips, D. R. Thakker, W. Egan, Synthesis, Hydrolytic Behavior, and Anti-HIV Activity of Selected Acyloxyalkyl Esters of Trisodium Phosphonoformate (Foscarnet Sodium) , J. Pharm. Sci. 1994, 83, 1269- 1273. 

Historically, the thermal transesterification of (-)-ethyl p-toluene-sulfinate 224 with n-butanol affording (+)-n-butyl p-toluenesulfinate 225 described by Phillips in 1925 (100) is the first nucleophilic substitution reaction at chiral sulfur involving a Walden-type inversion. The evidence for inversion of configuration in this reaction was based on the assumption that both (-)-esters 224 and 225 obtained from the kinetic resolution have the same configuration. 

Zhu J, Phillips SP, Feng YF, Yang X (2006) Phthalate esters in human milk concentration variations over a 6-month postpartumtime. Environ Sci Technol 40 5276-5281... 

Vitamin D3 [67-97-0] 384.6, m 83-85°, [a fs°46 +126° (c 2, EtOH). Converted into their 3,5-dinitrobenzoyl esters, and crystd repeatedly from acetone. The esters were then saponified and the free vitamins were isolated. [Laughland and Phillips AC 28 817 7956]. 

The Phillips catalyst is usually made by impregnating a chromium compound onto a porous, high-surface-area silicate carrier and then calcining in dry air at 500-900° C (14) (Fig. 1). This latter step is an activation that converts the chromium into a hexavalent surface chromate or perhaps dichromate ester. Because each chromium atom is individually attached to the... 

Maki BE, Chan A, Phillips EM, Scheldt KA (2007) Tandem oxidation of allylic and benzylic alcohols to esters catalyzed by N-heterocyclic carbenes. Org Lett 9 371-374... 

The rate of incorporation of cupric ions into protoporphyrin dimethyl ester was found to be accelerated by a factor of ca. 20,000 in the presence of aqueous micellar sodium dodecyl sulfate (2-5%) relative to that in 5% CTAB (Lowe and Phillips, 1961). This rate acceleration was found to be the consequence of a change in the activation entropy and was attributed to micellar solubilization of the porphyrin ester such that the pyrrole nitrogen atoms are located in the Stern layer in close proximity to cupric ions electrostatically attracted to the anionic micellar surface. The rate of incorporation of cupric ions in the presence of NaLS was also found to be catalyzed and inhibited by chelating agents (Lowe and Phillips, 1961, 1962). 

This work showed that the stereochemistry of the 3-covalent sulfur in these metallic coordination compounds was not essentially different from that in the sulfinic esters, the sulfoxides, and the sulfilimines, which were resolved by Phillips et al. (4, 13j 47). 

Phillips, A.M.M.M., and Modro, T.A., Phosphonic systems. Part 2. Functional group and skeleton modifications in diethyl esters of 2-propenyl (and 2-pentenyl) phosphonic acids. Phosphorus, Sulfur Silicon Relat. Elem., 55, 41, 1991. 

Iyer, R.P., Boal, J.H., Phillips, L.R., Thakker, D.R., and Egan, W., Synthesis, hydrolytic behavior, and anti-HIV activity of selected acyloxyalkyl esters of trisodium phosphonoformate (foscarnet sodium), J. Pharm. Sci., 83, 1269, 1994. 

Smith, A.B., III, Yager, K., Phillips, B.W., and Taylor, C.M., Asymmetric synthesis of diethyl (R)-(-)-(l-amino-3-methylbutyl)phosphonate (Phosphonic acid, (l-amino-3-methylbutyl)-, diethyl ester, (R)-), Org. Synth., 75, 19, 1998. 

Shake the ester with saturated NaHC03 solution until neutral, washed it with water, dry with MgS04 and distil it. The ester has also been purfied by repeated fractional distillation through an efficient column or spinning band column. [Timmermann Hennant-Roland J Chim Phys 52 223 1955, Mumford Phillips J Chem Soc 75 1950, H NMR Crawford Foster Can J Phys 34 653 1956, Beilstein 2 IV 152.]... 

One old and difficult issue pertaining to Phillips catalysts is the nature of the surface Cr(VI) species. Cr atoms could conceivably be attached in isolated chromate species, or they could bind in pairs as dichromate (or perhaps as higher polychromates). The question is important to our understanding of the catalyst because some researchers have suggested that polymerization requires two Cr centers. Thus, polymerization mechanisms involving paired Cr atoms have sometimes been proposed [76-92]. It was even suggested that unsupported organic Cr(VI) esters exhibit no activity precisely because they are chromate-like structures [76]. 

Organic sources of Cr(VI) have also been investigated as the chromium source. Baker and Carrick [148] first investigated bis(triphenylsilyl) chromate as a homogeneous model for the surface chromate structures postulated to exist on the Phillips catalyst. This chromate ester is quite stable, but like Cr(VI) /silica, it can also be reduced by olefins under polymerization conditions to give the corresponding aldehyde and Cr(II) or Cr(III). Thus, it mimics the behavior of Cr(VI)/silica in many respects [149]. Bis(triphenylsilyl) chromate does catalyze ethylene polymerization,... 

---