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In the present study we determined the concentrations and compositions of a suite of isopropylated and tert-butylated triarylphosphate ester (ITP and TBPP) isomers in house dust from the city of Guangzhou located in South China and the city of Carbondale in Midwestern United States. These two groups of organophosphate esters (OPE) are structurally analogous to triphenyl phosphate (TPHP), but have rarely been investigated for environmental occurrences and human exposure risks. The majority of target ITP and TBPP isomers were 100% detected in house dust from the two locations. Median concentrations of ΣITPs (including all ITP isomers) and ΣTBPPs (including all TBPP isomers) were 63.4 ng/g (range: 16.0–500 ng/g) and 35.4 ng/g (8.1–198 ng/g) in South China house dust, respectively, compared with 476 ng/g (140–1610 ng/g) for ΣITPs and 81.3 ng/g (35.2–800 ng/g) for ΣTBPPs in Midwestern U.S. dust. The profiles of ITP or TBPP isomers were similar between the two locations and were dominated by 2-isopropylphenyl diphenyl phosphate (2IPPDPP) and 4-tert-butylphenyl diphenyl phosphate (4tBPDPP), respectively. Although the levels of ΣITPs and ΣTBPPs were generally one order of magnitude lower than those of TPHP in the same dust samples, the broad occurrences of most of these isomers in house dust from the two locations likely suggest their wide applications in household consumer products. Estimated intakes of ΣITPs and ΣTBPPs via dust ingestion were generally three orders of magnitude lower than the reference dose proposed for TPHP. However, these emerging OPE chemicals merit continuous environmental surveillance, given their possible applications as specific commercial mixtures or as components/impurities in other flame retardant/plasticizer mixtures.

Substitution of diethyl and diphenyl benzylic phosphates, Alk-CH(Ar1)OP(O)(OR)2 (R = Et, Ph; Alk = Me, Et, i-Pr; Ar1 = aryl), with the anions derived from Ar2CH2 (Ph2CH2,9H-xanthene and fluorene) and n-BuLi at –15 °C was studied. For phosphates with Me as an Alk, diethyl phosphates produced Me-CH(Ar1)CH(Ar2)2 (Ar1 = 4-halo-, 4-CN, 4-Me-, 2-Me, 2-Br-, 3-MeO-phenyl and 2-naphthyl). However, an unwanted substitution at the Et group competed with phosphates of Alk = Et- and i-Pr. Fortunately, the corresponding diphenyl phosphates cleanly underwent the desired substitution. Two enantioenriched phosphates, MeCH(Ph)OP(O)(OEt)2 and EtCH(Ph)OP(O)(OPh)2, proceeded with complete inversion of the stereochemistry.

The synergistic effect of mixed Cyanex 572 and n-octyl diphenyl phosphate for Th(IV) extraction from nitric acid solution has been investigated in this paper. The effect of acidity together with mole fraction of extractant on the synergistic effect was studied. Based on the obtained results, the maximal synergistic enhancement coefficient reaches 12.40 at a ratio of 1:2 of Cyanex 572 and n-octyl diphenyl phosphate. Under the experimental conditions, the phase separation performance, stripping property and selectivity of Th and REE in the mixed extraction system are better than those from individual Cyanex 572 or n-octyl diphenyl phosphate system. The synergistic extraction mechanism for Th(IV) in nitric acid medium is proposed as Th aq 4 + + HA 2 org + 2.5 B org + 3 NO 3 − aq ↔ K ex Th NO 3 3 HA 2 B 2.5 org + H aq + . The mixed extraction system is successfully used for the separation of Th(IV) and REE(III) from the industrial feed solution leached from ion-absorbed type rare earth mineral waste residue. Lower stripping acid, stronger extraction ability, better phase separation performance and selectivity provide the synergistic extraction system with good application prospects.

Levels of eleven organophosphate esters (OPEs) were measured in particle phase atmospheric samples collected at Bohai Sea and northern Yellow Sea in China. The concentration of ∑11OPEs in atmospheric particles ranged from 426 to 3933 pg/m3, with the mean concentration of 1412 pg/m3. Tris(1-chloro-2-propyl) phosphate (TCPP) and triphenyl-phosphine oxide (TPPO) were the most abundant OPE congeners measured, and the individual concentrations of trimethyl phosphate (TMP), tri-iso-butyl phosphate (TiBP), tri-n-butyl phosphate (TnBP), tris(1,3-dichloro-2-propyl) phosphate (TDCP), triphenyl phosphate (TPhP), 2-ethylhexyl diphenyl phosphate (EHDPP), TPPO and tri-m-cresyl phosphate (TMTP) in atmospheric particles above the Bohai Sea were higher than those above the northern Yellow Sea. The estimated atmospheric dry deposition fluxes ranged from 202 to 1869 ng/m2/day. Up to 18.3 ± 12.5 ton/year of OPEs can be loaded to the Bohai Sea.

Indoor environments provide sources of exposure to organophosphate flame retardants (PFRs), which are artificially synthesized fire-protecting agents used as additives in interior products. As public spaces, hotels are required to meet stricter fire-precaution criteria. As such, room attendants may be exposed to higher levels of PFRs. Our goal was to characterize the exposure of hotel room attendants to PFRs by measuring metabolites in their urine and the corresponding parent PFRs in dust and hand-wipes collected from 27 hotels located in Wuhan City, China. The exposure of the attendants was found to be omnipresent: urinary metabolites of PFRs, such as DPHP (diphenyl phosphate), BDCIPP (bis(1,3-dichloro-2-propyl) phosphate), and DoCP (di-o-cresyl phosphate) & DpCP (di-p-cresyl phosphate) were detected with high frequency (87%, 79% and 87%, respectively). We observed that metabolites in post-shift urine were consistently present at higher levels than those in the first morning voids (p < 0.05 for BDCIPP and DPHP). Regarding external exposure, 10 PFRs were determined in both dust samples and hand-wipes, with TCIPP (tris(2-chloroisopropyl) phosphate) being the most abundant compound in both matrices. The levels of PFRs in hand-wipes and dust samples were not correlated. PFRs in dust and their corresponding urinary metabolites were not significantly correlated, while a moderate significant correlation of TDCIPP (tris(1,3-dichloro-2-propyl) phosphate) in hand-wipes and its urinary metabolite, BDCIPP, was observed in both morning void samples (p = 0.01) and post-shift urine (p = 0.002). Moreover, we found that participants from high-rise buildings (defined as > 7 stories) had significantly higher BDCIPP and DPHP concentrations than those from low-rise buildings. A possible reason is that high-rise buildings may use high-grade fireproof building materials to meet stricter fire restrictions. Overall, these results indicate that PFRs exposure in hotels is a contributor to the personal exposure of hotel room attendants. (C) 2018 Elsevier Ltd. All rights reserved.

Organophosphate flame retardants (PFRs) and bisphenol A (BPA) were measured in indoor dust and PM2.5 samples from nine kindergartens and two primary schools in Hong Kong. The average levels of PM2.5 ranged from 4.0E+03 ng/m3 to 1.5E+04 ng/m3. Average levels of PFRs (from 1.5 ng/m3 to 20 ng/m3 in PM2.5; from 8.0E−02 μg/g dw to 2.4 μg/g dw in dust) and BPA (from 6.4E−01 ng/m3 to 1.0 ng/m3 in PM2.5; from 1.0E−02 μg/g dw to 2.0E−01 μg/g dw in dust) were detected in most of the sampling sites. Tri-(2-Chloroethyl) phosphate (TCEP), tris(1,3-Dichloro-2-propyl) phosphate (TDCP), tris-(chloroisopropyl) phosphate (TCPP), and triphenyl phosphate (TPHP) were present in low levels in PM2.5 with medians of 16, 14, 8.7, and 3.2 ng/m3, respectively. In dust, the medians were 1.5E−01, 5.5E−02, 5.9E−01, 8.6E−01, and 8.5E−02 μg/g dw for TCEP, TCPP, TDCPP, TPHP, and 2-ethylhexyl diphenyl phosphate, respectively. The medians of BPA were 6.4E−01 ng/m3 and 7.4E−02 μg/g dw for PM2.5 and dust, respectively. A positive correlation was found between indoor PM2.5 and dust in the levels of TCEP (r = 0.85; p = .05). In the individual classroom in this survey, the predominant PFRs were similar, that is, TDCP and TCEP in indoor PM2.5 while TPHP and TDCP in dust. TPHP and TCEP in primary schools were obviously lower than those in kindergartens. The estimated daily intakes via PM2.5 and dust for all selected PFRs ranged from 1.3E−4 μg/kg/d to 2.0E−02 μg/kg/d, and the value of less than the detection limit at 3.5E−4 μg/kg/d was found for BPA. The EDI values of TPHP in dust non-dietary intake fraction were higher than those in the others. Calculated hazard indices (EDI/RfD) ranged from 4.8E−06 and 5.5E−03, showing that PFRs and BPA in PM2.5 and dust presented no health risks to children.

Organophosphate esters (OPEs) are widely used in household products as flame retardants or plasticizers and have become ubiquitous pollutants in environmental media. However, little is known about OPE metabolites in humans, especially in children. In this study, eight OPE metabolites were measured in 411 urine samples collected from 6 to 14-year-old children in South China. Bis(2-chloroethyl) phosphate (BCEP), bis(1-chloro-2-propyl) phosphate (BCIPP) and diphenyl phosphate (DPHP) were the dominant OPE metabolites, and their median concentrations were 1.04, 0.15 and 0.28 μg/L, respectively. The levels of urinary OPE metabolites in the present study were much lower than those in participants from other countries, with the exception of BCEP, suggesting widespread exposure to tris(2-chlorethyl) phosphate (TCEP, the parent chemical of BCEP) in South China. No significant difference in the concentrations of any of the OPE metabolites was observed between males and females (p > .05). Significant negative correlations were observed between age and BCEP, BCIPP, bis(1,3-dichloro-2-propyl) phosphate (BDCIPP), di-o-cresyl phosphate (DoCP) and di-p-cresyl phosphate (DpCP) (DCP), or DPHP (p

Phosphate flame retardants (PFRs) are ubiquitous chemicals in the indoor environment. Diphenyl phosphate (DPHP) is a major metabolite and a common biomarker of aryl-PFRs. Since it is used as a chemical additive and it is a common impurity of aryl-PFRs as well as a degradation product, its presence in indoor dust as an additional source of exposure should not be easily ruled out. In this study, DPHP (and TPHP) are measured in indoor dust in samples collected in Spain and in the Netherlands (n=80). Additionally, the presence of other emerging aryl-PFRs was monitored by target screening. TPHP and DPHP were present in all samples in the ranges 169–142,459ng/g and 106–79,661ng/g, respectively. DPHP concentrations were strongly correlated to the TPHP levels (r=0.90, p

In this article, some novel extractants were synthesized for the separation of Th and rare earth (RE). Among the synthesized neutral organophosphorus extractants, n-octyl phosphate diphenyl (ODP) revealed excellent extraction efficiencies and selectivities for Th(IV). Moreover, loading capacity of ODP for Th(IV) (0.015 mol/L) reached 130 mg/L, the loading capacities and speed were higher and faster than those of P507, TBP and C272, respectively. Furthermore, the loaded Th(IV) could be fully stripped by sulfuric acid and hydrochloric acid. The novel extractant ODP has been indicated to be an efficient extractant for the separation of Th, REs and Fe from ion-adsorption type RE minerals, which reveals significances in the fields of resource, environment and energy.

The use of triphenyl phosphate (TPhP) as a flame retardant or plasticizer has increased during the last decade, resulting in widespread human exposure without commensurate toxicity assessment. The main objectives of this study were to assess the in vitro effect of TPhP and its metabolite diphenyl phosphate (DPhP) on the adipogenic differentiation of 3T3-L1 cells, as well as glucose uptake and lipolysis in differentiated 3T3-L1 adipocytes. TPhP increased pre-adipocyte proliferation and subsequent adipogenic differentiation of 3T3-L1 cells, coinciding with increased transcription in the CEBP and PPARG pathway. Treatment of mature adipocytes with TPhP increased the basal- and insulin stimulated- uptake of the glucose analog 2-[N (−7-nitrobenz-2-oxa1, 3-diazol-4-yl) amino]-2-deoxy-d-glucose (2-NBDG). This effect was ablated by inhibition of PI3K, a member of the insulin signaling pathway. DPhP had no significant effect on cell proliferation and, compared to TPhP, a weaker effect on adipogenic differentiation and on 2-NBDG uptake. Both TPhP and DPhT significantly enhanced the isoproterenol-induced lipolysis, most likely by increasing the expression of lipolytic genes during and after differentiation. This study suggests that TPhP increases adipogenic differentiation, glucose uptake, and lipolysis in 3T3-L1 cells through endocrine and noradrenergic mechanisms.

Environmental pollution has become a concern for public health. As endocrine disruptors, organophosphate esters (OPEs) causes many diseases via human exposure. However, there is limited research on the risk of OPE exposure to female-specific cancers. Blood measurements are biomarkers for chemical exposures by their definition. Thus, in the present study, 11 OPEs were analyzed in the plasma of patients with 4 female-specific tumors. 2-Ethylhexyl diphenyl phosphate (EHDPP) was detected at the highest levels in all groups. The Spearman correlation test results showed significantly positive correlations between some OPEs in each group, which indicated that those OPEs had similar sources and/or behaved similarly in the patients of each group. However, compared with different patient groups, obvious differences in the correlation results were noted, implying the differences in the metabolism of OPEs between different groups. The results of the correlation analysis showed that EHDPP concentration was associated with the risk of breast cancer (p 0.05), while tri-n-butyl phosphate (TNBP), tris (methylphenyl) phosphate (TMPP), triphenyl phosphate (TPHP), and EHDPP concentrations were associated with the risk of cervical cancer (p 0.05 or p 0.01). These findings indicated that OPEs were associated with the risk of breast and cervical cancer.

Triphenyl phosphate (TPP or TPhP) is commonly used as an additive plasticizer or organophosphate flame retardant (OPFR) in consumer products including nail polish. We evaluated exposure to TPhP from 12 nail salon technicians working at four nail salons located in California over a period of two work days. Bulk samples of 15 nail polishes and other nail products were collected. Study participants also provided two personal air samples, two hand wipe samples (pre- and post-shift on day two), and two urine samples (pre-shift day one and post-shift day two). The geometric mean (GM) of TPhP air sampling concentrations was 7.39 ng/m3. Post-shift TPhP hand wipe concentrations (GM 1.35 μg/sample) were significantly higher (p = 0.024) than pre-shift hand wipe concentrations (GM 0.29 μg/sample). Diphenyl phosphate (DPP or DPhP), a urinary metabolite of TPhP used in this study as a biomarker of exposure, was detected in all post-shift urine samples and 75% of urine pre-shift samples. DPhP post-shift concentrations (GM 1.35 μg/g creatinine) were significantly higher than pre-shift concentrations (GM 0.84 μg/g creatinine; p = 0.012). In addition, DPhP post-shift concentrations were correlated with TPhP post-shift hand wipe concentrations, suggesting dermal contact may be a relevant exposure pathway for nail salon workers.

A new reagent, 3-azaspiro[5,5]undecan-2,4-dioxo-3-yl diphenyl phosphate (ASUD-diphenyl phosphate) is described for the synthesis of N-protected amino acid-ASUD esters which are active esters useful in the synthesis of peptides. This compound was synthesized by reacting N-hydroxy-3-azaspiro[5,5]undecane-2,4-dione (HO-ASUD) with diphenyl chlorophosphate in the presence of a base at room temperature and was obtained in high yields. The ASUD-diphenyl phosphate reagent reacts with N-protected amino acids under mild conditions to give the corresponding ASUD active esters, while preserving the enantiomeric purity of the amino acid. The new reagent is a stable crystalline compound and eliminates the need for DCC, a potent skin allergen, used previously for the synthesis of N-protected amino acid-ASUD ester.

In this study, 45 indoor dust samples and four particulate samples from air-conditioner filters were collected from four different indoor environments in Guangzhou, China, and the concentration and composition of organophosphate tri-esters (OPEs) and organophosphate di-esters (Di-OPs) were determined. Eight of the 10 target OPEs were detected in indoor dust at different detection frequencies (DFs), with tris(2-chloroisopropyl) phosphate and tris(2-chloroethyl) phosphate being the main components. Seven target Di-OPs were detected at different DFs, with diphenyl phosphate being the dominant compound. The total OPEs (∑8 OPEs) and total Di-OPs (∑7 Di-OPs) concentrations varied from 726 to 39,312 ng/g and 68.8-14,766 ng/g, respectively. The ∑8 OPEs concentrations in instrumental houses were significantly higher (p 0.001) than in three other indoor environments. The varying strengths of the correlation between Di-OPs and their respective parent OPEs was suggestive of their emission sources (e.g., direct application, impurities in OPE formulas, and OPE degradation). The hazard index (HI) values of individual OPEs in residential house were lower than 1, the results suggested a limited human health risk from individual OPEs. However, the total HI value (∑HIs) of OPEs was approximately 1 based on a high exposure scenario and suggested a low risk for toddlers.

A total of 24 surface sediment samples were collected from Liao River, Northeast China. The concentration, spatial distribution, potential source, and ecological risk of 13 organophosphate esters (OPEs) flame retardants and plasticizers were analyzed. The total concentrations of OPEs varied considerably, ranging from 19.7 to 234 ng g−1 dry weight (dw), with the mean concentrations of 64.2 ± 52.2 ng g−1 dw. The OPEs pollution was increasing from upstream to downstream of Liao River. Compared with other sediments of rivers and lakes all over the world, Liao River has been seriously contaminated by OPEs, especially tributyl phosphate (TNBP) and tri-butoxyethyl phosphate (TBOEP). TNBP was the most abundant OPEs, followed by TBOEP and triphenylphosphine oxide. Their mean relative contributions were 26.3%, 12.4% and 11.6%, respectively. Positive matrix factorization indicated that OPEs in sediments from Liao River might be derived from plastic, textile, and polyurethane foam, anti-foam agent, hydraulic fluids, and coatings, indoor release, and chemical process emission. The risk of potential adverse effects of each individually OPEs on aquatic organisms were low (risk quotient less than 0.1). 2-Ethylhexyl diphenyl phosphate was the main substance causing risk.

A general method to synthesize N -aryl pyrrole derivatives was realized via the reactions of 2-(3-pyrroline-1-yl)arylaldehydes with indoles under acidic conditions, which underwent [1,5]-hydride shift/isomerization process. The desired products could be obtained in good to high yields with a wide substrate scope.

Three oligomeric organophosphorus flame retardants (o-PFRs), eight monomeric PFRs (m-PFRs), tetrabromobisphenol A (TBBPA), and polybrominated diphenyl ethers (PBDEs) were identified and quantified in surface soils and river sediments around the e-waste recycling area in Bui Dau, northern Vietnam. Around the e-waste recycling workshops, 1,3-phenylene bis(diphenyl phosphate) (PBDPP), bisphenol A bis(diphenyl phosphate) (BPA-BDPP), triphenyl phosphate (TPHP), TBBPA, and PBDEs were dominant among the investigated flame retardants (FRs). The respective concentrations of PBDPP, BPA-BDPP, TPHP, TBBPA and the total PBDEs were 6.6-14000 ng/g-dry

To assess the exposure of flame retardants (FRs) for school-children, organophosphorus flame retardants and plasticizers (PFRs) and organobromine flame retardants (BFRs) were determined in the indoor dust samples collected from elementary schools and domestic houses in Japan in 2009 and 2010. PFRs were detected in all the dust samples analyzed and the highest concentration of total PFRs was thousand-fold higher than that of BFRs. Among the PFRs, tris(butoxyethyl)phosphate (TBOEP) showed the highest concentration with a median (med.) of 270,000 ng g(-1) dry weight (3700-5,500,000 ng g(-1) dry weight), followed by tris(methylphenyl)phosphate (TMPPs)>triphenyl phosphate (TPHP)=tris(1,3-dichloro-2-propyl)phosphate (TDCIPP)=tris(2-chloroisopropyl)phosphate (TCIPP)=tris(2chloroethyl)phosphate (TCEP)>ethylhexyl diphenyl phosphate (EHDPP). Significantly higher concentrations of TBOEP, tri-n-butyl phosphate (TNBP), TPHP, TMPPs, and total-PFRs were found in dust samples from elementary schools than from domestic houses. It might be due to that higher concentrations of TBOEP (as leveling agent) were detected from the floor polisher/wax products collected in those elementary schools. On the other hand, significantly higher concentrations of TCEP, TCIPPs, and total chloroalkyl-PFRs were found in domestic houses than in elementary schools. Exposure assessments of PFRs via indoor dust from elementary schools and domestic houses were conducted by calculating the hazard quotient (HQ). Among PFRs, HQs for TBOEP exceeded 1 (higher than reference dose: RfD) and its highest value was 1.9. To reduce the intake of TBOEP by school-children, it is recommended that the use of floor polisher/wax containing TBOEP be reduced in schools.

The flame retardance of co-cured blends of an unsaturated polyester with various phenolic resoles is improved by the addition of the phosphorus-containing flame retardants: resorcinol bis(diphenyl phosphate), bisphenol-A bis(diphenyl phosphate) and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide. Cone calorimetric studies indicate reductions in important parameters such as total heat released and peak heat release rate. However, although the improved flame retardancy is accompanied by increased char yields, smoke evolution is also increased indicating contributions from both condensed-phase and gas-phase mechanisms of flame retardance. Improvements in flame retardance are particularly marked in systems in which the unsaturated polyester is at least partly compatible with the phenolic resole; TGA studies indicate that this may be due to better retention of the flame retardant in the condensed phase in the more compatible systems.

WOS: 000288773900022, Six 5.0 mol% crosslinked poly[(styrylmethyl)hexadecyldimethylammonium chloride] latexes containing 8-67% quaternization were synthesized via two-stage process and used as supports for o-iodosobenzoate (IBA) catalyst in the hydrolysis of model organophosphate compound p-nitrophenyl diphenyl phosphate (PNPDPP). The hydrodynamic diameters of the cationic latexes were less than 200 nm. The rate of the hydrolysis of PNPDPP greatly increased in the presence of the cationic latex particles and strongly depended on the degree of quaternization and amount of the latex as well as pH, type of buffer, and ionic strength of the medium. As the quaternization percentage of the latexes increased, the rates of the hydrolysis increased. The pseudo-first-order and second-order-rate constants of the hydrolysis reaction carried out with different amounts and type of cationic latexes at pH 7.0, 8.0 and 9.0 in different buffer solutions at 25 degrees C were determined. 1.0 x 10(-5) M IBA in 0.25 mg/mL of QL-67 latex enhanced the rate of the hydrolysis of 1.0 x 10(-5) M PNPDPP about 5670 times in TAPS buffered solution at pH 8.0 compared to the one in buffered solution and 1590 times in the presence of IBA alone in TAPS buffered solution. The highest second-order-rate constant k(cat) of 21200 +/- 1100 M-1 s(-1) was obtained when 0.25 mg/mL of QL-67 was employed in the hydrolysis reaction at pH 8.0, Scientific Research Projects Commission at Anadolu University [1001F28], Financial support from the Scientific Research Projects Commission at Anadolu University (Grant No. 1001F28) is gratefully acknowledged.

Studies on thermal-oxidative stability of a phosphorated antioxidant, synthesized from a natural and renewable resource cashew nut shell liquid (CNSL) was investigated, using a classical thermoanalytical method-thermogravimetric (TG/DTG) in air atmosphere. Its use as an antioxidant agent on the mineral oils NH10 and NH20 was evaluated in comparative studied with a commercial product (diphenyl phosphate – Aldrich). The addition of 1.2–2.0 wt% of phosphorated cardanol compound to the mineral oils has improved their thermal-oxidative stability on 14–18 °C, respectively. The occurrence of major thermal degradation events at higher temperatures ( T max ) on additivated oils is an excellent indication of the phosphorated cardanol compound antioxidant properties.

Kinetic study of the reaction of p-nitrophenyl diphenyl phosphate with 2-aminomethylphenols and the basic hydrolysis of ethyl p-nitrophenyl ethyl phosphonate have shown that in direct micelles the concentration factors is mainly responsible for the acceleration of nucleophilic substitution reaction while the micellar microenvironment negatively affects the reactivity and results in a diminution in the micellar rate effect. The considerable contribution to the micellar catalysis is made by the acid-base equilibrium shift of reagents. On the contrary, in reverse aggregates the micellar microenvironment favours the reaction and mostly underlies the mechanism of the catalysis, while the concentration factors plays a minor role.

Quinolines 3a–f, 5a–f, and dibenzo[b,f][1,5]diazocines 4, 6 were synthesized in the presence of 0.5 equiv. of diphenyl phosphate (DPP) under microwave irradiation. The obtained yield of 6,12-diphenyl-dibenzo[b,f][1,5]diazocine 4 was higher when using anhydrous DPP than when using HCl, H3PO4, and CH3COOH.

Acetylated α-glycosyl nitrates were efficiently converted under mild conditions into protected β-glycosyl phosphates by treatment with cesium dibenzyl phosphate or into thermodynamically more stable α-glycosyl phosphate derivatives upon interaction with cesium diphenyl phosphate. These reactions were found to be applicable both to 2-azido-2,6-dideoxy- and 2-azido-2-deoxygalactopyranosyl nitrates as well as to 6-deoxygalactopyranosyl and galactopyranosyl derivatives.

To enhance the safety of lithium ion batteries, 4-isopropyl phenyl diphenyl phosphate (IPPP) was explored as an additive in 1.0 M LiPF6/ethylene carbonate (EC) + diethyl carbonate (DEC) (1:1 wt.%). The electrochemical performances of LiCoO2/IPPP electrolyte/C cells were tested. And then the LiCoO2/IPPP electrolyte/C cells were disassembled and wrapped to detect the thermal behaviors using a C80 microcalorimeter. The results indicated that 5% and 10% IPPP content in the electrolyte can enhance the safety of lithium ion batteries. Furthermore, the electrochemical performances of LiCoO2/IPPP electrolyte/C cells become slightly worse by using 5% and 10% IPPP content electrolyte. Therefore, 5–10% IPPP content in electrolyte can enhance the safety of lithium ion batteries with minimum sacrifice in electrochemical performance.

The structure of 1-hydroxy-1,2,3-benzotriazolium diphenyl phosphate (HOBt/DPP) has been investigated by X-ray analysis. The compound crystallizes in the monoclinic space group P2 1 n with Z = 4 and the following lattice parameters: a = 11.711(2), b = 12.727(2) and c = 12.794(3) A , β = 105.12(2)°, V = 1840.9(6) A 3 . The structure was solved by direct methods and refined on F2 to R values of wR2 = 0.084 and R1 = 0.034 for 1985 observed reflections. HOBt/DPP has an ionic structure with very short OHO and NHO hydrogen bonds linking the different ions. Owing to these hydrogen bonds, infinite screw-shaped chains which are twisted parallel to the y-axis are formed.

The dibenzobarrelene iodosocarboxylate 6 is a powerful catalyst for the cleavage of p-nitrophenyl diphenyl phosphate in cetyltrimethylammonium chloride micellar solution at pH 8.

The protected guanosine and uridine derivatives (3a, 3b and 4) react with 1-(mesitylene-2-sulphonyl)-3-nitro-1,2,4-triazole (MSNT, 2a) to give 5a, 5b and 7, respectively: 9 is converted into 10 in the same way. The reactions proceed more rapidly in the presence of diphenyl phosphate.

Hydroxide ion cleavage of p -nitrophenyl diphenyl phosphate occurs at exovesicular and endovesicular sites of dihexadecyldimethylammonium ion vesicles. The endovesicular reaction can be eliminated upon alteration of the vesicle's permeability to hydroxide ions by the incorporation of cholesterol.

Experiments are reported showing that chronic feeding of either mono-2-cresyl diphenyl phosphate or diisopropyl phosphorofluoridate (DFP) to hens does not cause clinically observable delayed neurotic effects prior to a point when inhibition of neurotoxic esterase (NTE) of brain and spinal cord reaches 70–90%. These results are contrary to another study with diisopropyl phosphorofluoridate, which claims neuropathy without high inhibition, but are supported by results of chronic feeding experiments with tri- o -cresyl phosphate. The discrepancy cannot be attributed to differences in the strains of hens used.

Uptake, clearance and disposition of 14C-labelled 2-ethylhexyl diphenyl phosphate (EHDP) and 14C-diphenyl phosphate (DPP) by rainbow trout (Salmo gairdneri) were investigated using short-term static exposures. Bioconcentration factors of 1314 and 0.3 were calculated for EHDP and DPP, respectively. Highest levels of radioactivity were found in liver and intestine following exposure to 60 μg/L EHDP. A portion (up to 40%) of the radioactivity in each tissue was in the form of DPP while a similar portion was extractable with methanol but could not be identified.

The fate of a triaryl phosphate (ring-UL-14C-2-isopropylphenyl diphenyl phosphate) was examined in fathead minnows. Diphenyl phosphate was identified as a major metabolite in whole body fish samples. A significant portion of the radioactive residues appeared to be associated with biogenic compounds, indicating “in vivo” reactions of biochemicals with 14C-metabolites or 14C-ring cleavage of 2-isopropylphenyl diphenyl phosphate and subsquent incorporation into biochemical pathways.

5-Thio- d -glucopyranosyl phosphate was prepared by reaction of the acetylated glycopyranosyl bromide with silver diphenyl phosphate followed by hydrogenolysis of the phenyl groups and deacetylation. 5-Thio- d -glucopyranose 6-phosphate was prepared from methyl 5-thio-2,3,4,6-tetra- O -(trimethylsilyl)-α- d -glucopyranoside by preferential removal of the trimethylsilyl group at O-6 by methanolysis, phosphorylation with diphenyl phosphorochloridate, and removal of the trimethylsilyl and phenyl groups. Both phosphates were obtained crystalline as their dicyclohexyl-ammonium salts.

Total vapour pressures were measured between 25–45°C in the methyl diphenyl phosphate-hexane system and between 25–75°C in the methyl diphenyl phosphate-water system. From the obtained data, the activity coefficients and the excess free energies of mixing were calculated. Both systems show strong positive deviations from ideal behaviour, which are sufficient to produce phase separation.

A Norrish type-II reaction is proposed for the photorearrangement of allyl diphenyl phosphate to ortho -allylphenyl phenyl phosphate. In contrast to the type-II mechanism in carbonyl compounds, the reaction is postulated to proceed through a five-membered transition state to produce a phosphoranyl 1,3-biradical which subsequently rearranges to the observed product.