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The photoirradiation of toluene derivatives with two equivalents of bromine in benzotrifluoride–water provided a satisfactory yield of the corresponding benzoic acid derivatives. Either a fluorescent lamp, blue LED (454 nm), or UV LED (385 nm) was used for the photoreaction. The reaction pathway might proceed through the dibromination of benzylic carbon, generation of the benzylic radical via oxidative C–H abstraction, formation of benzoyl bromide, and hydrolysis of carboxylic acid.

Synthesis of sulfonyl halides using sodium hypochlorite pentahydrate (NaOCl·5H2O) crystals was studied in detail, considering the reaction rate and yield of the desired product. NaOCl·5H2O reacted with disulfides or thiols in acetic acid to produce sulfonyl chlorides. The yields of the desired sulfonyl chlorides were enhanced when the reaction was performed in (trifluoromethyl)benzene under a CO2 atmosphere. The generation of hypochlorous acid (HOCl) was essential for both reactions. Similarly, sulfonyl bromides were prepared via the reaction of disulfides or thiols with sodium bromide and NaOCl·5H2O crystals in acetic acid owing to the generation of hypobromous acid (HOBr). However, the reaction could not proceed in (trifluoromethyl)benzene under a CO2 atmosphere because bromine was produced instead of HOBr.

Pent-4-yn-1-ol was prepared with a high yield by the reaction of tetrahydrofurfuryl chloride with n-BuLi in t-BuOMe at 0 ˚C. Pent-4-en-1-ol was prepared with a high yield by either the reaction of tetrahydrofurfuryl chloride or tetrahydrofurfuryl bromide with lithium in tetrahydrofuran (THF) at temperatures from 0 ˚C to ambient temperature.

Heparin resistance (HR), defined as a decrease in heparin responsiveness, can result in adverse events with prolonged duration of surgery. Although some clinical risk factors have been suggested, the relationship with the surgical diagnosis is unclear. The aim of present study was to elucidate the clinical predictors of HR including the surgical diagnosis.This retrospective cohort study determined the incidence of HR (defined as activated clotting time [ACT]400 seconds after 250-350 IU/kg of heparin administration) and heparin sensitivity index (HSI) was calculated from the rate of change in ACT per heparin dose. Preoperative demographic data, medication history, and laboratory data also were analyzed.Single institution, tertiary care hospital.Adult patients who underwent cardiovascular surgery with cardiopulmonary bypass between January 2012 and September 2018.None.Of 287 patients, 88 (30.7%) were classified as HR. In univariate analysis, infective endocarditis (IE), platelet count, and serum fibrinogen and albumin levels were associated with HR. After adjustment for baseline ACT and initial heparin dose, IE (odds ratio 4.57, [95% CI: 1.10-19.1]; p = 0.037) and albumin ≤3.5 g/dL (3.17, [1.46-6.93]; p = 0.004) were associated independently with HR. Patients with IE had significantly lower HSI than those with other diseases. All HR patients were treated with additional heparin, and 17 of them received human antithrombin-III concentrate.Infective endocarditis and preoperative hypoalbuminemia were associated independently with HR. The optimal anticoagulation strategy for patients with these risk factors requires further investigations based on the authors' findings.

Aromatic, semiaromatic, and aliphatic polyesters were synthesized at moderate temperatures (25–80 °C) by the polymerization of divalent acyl-1,2,4-triazoles using 4-(dimethylamino)pyridine as a catalyst. The monomers were prepared from divalent acyl chloride in high yields, although some of them required that toluene and pyridine be used as solvents due to their high crystallinity. Melt polymerization in diphenyl ether was effective in affording semiaromatic and aliphatic polyesters. However, this method was not suitable for aromatic polyesters, as the reaction system became heterogeneous at 80 °C. Nevertheless, solution and interfacial polymerization reactions were effective in obtaining aromatic polyesters. The novel monomers provided polyester synthesis at moderate temperature without the use of any metal catalyst or halide monomers. The polymerization of divalent acyl-1,2,4-triazoles and diols/bisphenols afforded a series of aromatic, semiaromatic, and aliphatic polyesters. Compared with polymerization by transesterification, this polymerization proceeded irreversibly at relatively low temperature (

Practical preparations of dichloromethyl alkyl ethers are described, based on the reaction of alkyl formates with oxalyl chloride in the presence of N-methylformanilide. The method involves a simple procedure that does not require the use of harmful reagents. Dichloromethyl propyl and dichloromethyl butyl ethers represent secure synthetic equivalents to dichloromethyl methyl ether. Formylations of both electron-deficient and electron-rich aromatics with these dichloromethyl alkyl ethers in the presence of AlCl3, FeCl3, or TiCl4 have been systematically investigated. A plausible mechanism of formylation is discussed.

New preparations of crystalline Vilsmeier reagent (VR) and dichloromethyl propyl or butyl ether were developed. The methods are environmentally benign and applicable to large-scale synthesis. Formylations of 1H-pyrrole-2-carboxylates were achieved with these reagents, regioselectively affording the 4-formyl and 5-formyl derivatives in nearly quantitative yields.

A 9-year-old girl with Glenn circulation suffered from massive atelectasis of the left lung caused by bleeding during cardiac catheterization. The atelectasis resulted in frequent hypoxia leading to oxygen saturation (SpO2) of 40%-50%. In the intensive care unit, we performed a unilateral lung recruitment maneuver (ULRM) for 2 days. The ULRM involved placement of a bronchial blocker in the right main bronchus and application of continuous positive airway pressure to the left lung without hemodynamic deterioration. Eventually, SpO2 improved to 80%-85%. ULRM can be a treatment option for unilateral atelectasis in a child with Glenn circulation.

Bifunctional acyl-bis(1,2,4-triazole) functioned as a highly reactive and nontoxic, halogen-free monomer for polyester synthesis that did not require a metal catalyst. Isophthaloyl 1,2,4-triazole was prepared from the corresponding chloride and polymerized with 1,12-dodecanediol at 120 °C in the presence of 4-(N,N-dimethylamino)pyridine, resulting in polyester with high molecular weight (Mn = 48.3 × 103) as a colorless solid. The use of solvents such as diphenyl ether was effective to conduct the polymerization of monomers that would not melt at low temperature.

The novel oxidant of sodium hypochlorite pentahydrate (NaOCl·5H2O) crystals is now available for industrial and laboratory use. It is superior to conventional aqueous sodium hypochlorite solutions (aq. NaOCl). The crystalline material is 44% NaOCl and contains minimal amounts of sodium hydroxide and sodium chloride, and the aqueous solution, which is prepared from NaOCl·5H2O and water, has a pH of 11–12. Examples of the selective organic synthesis using NaOCl·5H2O involve the oxidations of primary and secondary alcohols, selective oxidations to sulfoxide and sulfone, oxidative cleavage of disulfide to sulfonyl chloride and bromide, oxaziridine synthesis, and oxidative dearomatization of phenols.

Sodium hypochlorite pentahydrate (NaOCl·5H2O) can be used toward the efficient glycol cleavage of trans-cyclic glycols, which are generally resistant to this transformation. Interestingly, the reaction of cis-cyclic glycols with NaOCl·5H2O is slower than that observed for the corresponding trans-isomer. This trans selectivity is in sharp contrast to traditional oxidants used for glycol cleavage. Acyclic glycols can also react efficiently with NaOCl·5H2O to form their corresponding carbonyl compounds in high yield.

Formylations of fluorine-containing aromatic compounds with dichloromethyl alkyl ethers have been investigated. Dichloromethyl propyl ether and dichloromethyl butyl ether have been applied for the formylation of fluorine-containing anisoles to give the corresponding aldehydes in good yields. Application of these ethers is preferable to that of methyl ether, which is prepared from volatile methyl formate. Reaction of fluorine-containing phenols with these dichloromethyl alkyl ethers did not give salicylaldehyde derivatives, leading instead to corresponding aryl formates in high yields. A plausible mechanism is discussed.

The novel oxidant of sodium hypochlorite pentahydrate (NaOCl·5H2O), which is now available for industrial and laboratory use has several advantageous properties. The crystalline material has 44% of NaOCl, contains minimal sodium hydroxide and sodium chloride, and the aqueous solution indicates pH 11–12. Herein, NaOCl·5H2O crystals are examined for use as an oxidant for primary and secondary alcohols, with or without nitroxyl radicals, in the presence or absence of phase-transfer catalysts. The pentahydrate crystals alone (without nitroxyl radicals) demonstrate a powerful oxidizing ability, converting secondary alcohols to the corresponding ketones. In the presence of TEMPO (2,2,6,6-tetramethylpiperidine 1-oxyl) or 1-Me-AZADO (1-methyl-2-azaadamantane N-oxy radical), sterically hindered secondary alcohols are oxidized without pH adjustment. A proposed mechanism for the oxidation is discussed.

Benzoyl-1,2,4-triazole underwent esterification with a primary alcohol in the presence of 4-(N,N-dimethylamino)pyridine (DMAP) catalyst at the rate comparable to benzoyl chloride. The kinetic study concluded that the reaction proceeds in a similar mechanism to carboxylic acid anhydride and is thus sensitive to the steric hindrance of alcohol. As the esterification of benzoyl-1,2,4-triazole did not afford acidic by-product and require an equimolar or more amount of base, it is effective for the protection of acid-sensitive alcohol and polyester synthesis.

Fluoroalkyl alcohols are effectivity oxidized to the corresponding fluoroalkyl carbonyl compounds by reaction with sodium hypochlorite pentahydrate in acetonitrile in the presence of acid and nitroxyl radical catalysts. Although the reaction proceeded slower under a nitroxyl radical catalyst- free condition, the desired carbonyl compounds were obtained in high yields. For the reaction with fluoroalkyl allylic alcohols, the corresponding α,β-epoxyketone hydrates were obtained in high yields.

Epidural analgesia (EDA) is an imperative modality for postoperative pain relief after major open abdominal surgery. However, whether EDA has benefits in laparoscopic surgery has not been clear. In this study, the effects of EDA and patient-controlled intravenous analgesia (PCIA) after laparoscopic distal gastrectomy (LDG) were compared.This was a retrospective study that included 82 patients undergoing LDG for gastric cancer. Patients received either EDA (n=67) or PCIA (n=15) for postoperative pain relief. Postoperative outcomes and analgesia-related adverse events were compared between the two modalities.EDA and PCIA patients showed no differences in the incidence of complications [9 (13%) vs. 2 (13%); P=0.99] and the length of postoperative hospital stay (9.6±4.5 d vs. 9.7±4.0 d; P=0.90), although the PCIA included poorer preoperative physical status (PS) patients. The number of additional doses of analgesics was higher in the EDA than in the PCIA (1.8±2.4 vs. 0.9±1.0; P=0.01), although postoperative pain scores were similar in the 2 groups. Though the time to first passage of flatus was shorter in the EDA (P0.05), more EDA patients developed postoperative hypotension as an adverse event (P0.01). The full mobilization day and the day of oral intake tolerance were not significantly different between the 2 groups after surgery.After LDG, EDA may not be indispensable, while PCIA may be the optimal modality for providing safe and effective postoperative analgesia and recovery.

Oxidation of sulfides with sodium hypochlorite pentahydrate crystals (1.1 equiv) in an aqueous acetonitrile solution selectively produces the corresponding sulfoxides in high yields. This procedure is catalyst-free and environmentally benign.

An environmentally benign and practical preparation method for the Vilsmeier-Haack reagent (VH) has been developed by using phthaloyl dichloride with DMF in toluene or 2-chlorotoluene. Phthalic anhydride as the byproduct was recovered in high yield by simple filtration. Some aromatic acids have been transformed into the corresponding acid chlorides in good yields by employing the isolated VH. Treatment of primary or secondary alcohols with VH gave alkyl formates or alkyl chlorides by depending on the reaction conditions.

The novel oxidant of sodium hypochlorite pentahydrate (NaOCl·5H2O), which is now available for industrial and laboratory use has several advantageous properties. The crystalline material has 44% of NaOCl, contains minimal sodium hydroxide and sodium chloride, and the aqueous solution indicates pH 11–12. Herein, NaOCl·5H2O crystals are examined for use as an oxidant for primary and secondary alcohols, with or without nitroxyl radicals, in the presence or absence of phase-transfer catalysts. The pentahydrate crystals alone (without nitroxyl radicals) demonstrate a powerful oxidizing ability, converting secondary alcohols to the corresponding ketones. In the presence of TEMPO (2,2,6,6-tetramethylpiperidine 1-oxyl) or 1-Me-AZADO (1-methyl-2-azaadamantane N-oxy radical), sterically hindered secondary alcohols are oxidized without pH adjustment. A proposed mechanism for the oxidation is discussed.

With the aim of enhancing the soil resistance of polypropylene (PP) fibers, polydimethylsiloxane (PDMS) and/or oleamide (OA) were added, and the soiling and wear resistances of the obtained fibers were evaluated. Films made from PP with the addition of PDMS and/or OA were fabricated and their water repellencies were evaluated by using droplets to measure their contact angles. The water contact angle increased with increasing amount of PDMS and/or OA added to PP. These blended resins were then used to produce fibers, which were in turn used to form fabrics. The soil resistances of these fabrics were evaluated by immersing them in aqueous solutions of a water-soluble artificial soiling substance for 1 min. Fiber G, for which both PDMS and OA had been added to PP, had a soiling ratio that was about 8–15% lower than that of pure PP fibers to which nothing had been added. Longer immersion of 24 h resulted in Fiber E, for which only PDMS had been added, having the lowest soiling ratio. In contrast, Fibers L and G (produced by adding OA) had relatively high soiling ratios when immersed for a long time. The wear resistances of knitted fabrics were evaluated using an abrasion tester. Fabric made from pure PP fibers had holes after 20 cycles of abrasion, whereas fabrics formed from fibers to which PDMS and/or OA had been added did not have holes even after 100 cycles of abrasion, which represents a remarkable improvement in wear resistance.

The reaction of disulfides or thiols with sodium hypochlorite pentahydrate in acetic acid efficiently provided the corresponding sulfonyl chlorides in high yields.

Dichloromethyl alkyl ethers have been synthesized from alkyl formates (C1–C4) and oxalyl chloride in the presence of catalytic amount of N -methylformanilide. N , N -Dimethylformamide is not suitable for the reaction. The method has the advantages of simple experimental procedure, which is applicable to large scale synthesis, without use of harmful reagents.

Oxidation of disulfides or thiols with sodium hypochlorite pentahydrate gives sulfonyl chlorides in an environmentally benign and economical manner.

Sodium hypochlorite pentahydrate crystals containing less free sodium hydroxide and sodium chloride have been developed as an improved oxidant. Primary and secondary alcohols have been oxidized to the corresponding aldehydes and ketones with ­NaOCl·5H2O in the presence of TEMPO/Bu4NHSO4. This new oxidation method does not require pH adjustment and is applicable to sterically hindered secondary alcohols.

The establishment of recycling systems and the reduction of various fiber wastes are strongly required to create a truly recycling society. In recent years, antibacterial functionality in products such as household articles have become widely used because of the rising demand for cleanliness and comfort in our lives. Therefore the amount of antibacterial waste fibers is expected to increase in the near future. With this trend in mind, this paper focuses on the use of PET fiber waste containing antibacterial agents in producing useful PET fiber reinforced PP thermoplastic composites.The PET waste fibers containing antibacterial agents were cut into 50mm lengths and mixed with a PP web by using a carding machine to make PET/PP webs with 0-70 weight percent of PET fiber (Wf). Samples were compression molded at a molding temperature between 180∼250°C. The antibacterial and the mechanical properties of the PET/PP composites were evaluated.The results of antibacterial tests showed that the antibacterial activity of the composites increased with increasing Wf. The composites with large Wf showed high antibacterial activity at short times. The bending strength of composites with Wf=10∼40% was larger than that of the neat PP matrix, and showed a maximum value at Wf=40% of about 1.6 times that of the neat PP matrix. The Izod impact value also increased notably with increasing Wf. It was concluded that the molding system devised here was an effective method for the recycle of PET fiber waste containing antibacterial agents in composite materials.

The purpose of this study is to investigate the spinnability, biodegradability and antibacterial properties of biodegradable polymers containing a silver-based antibacterial agent. The biodegradable polymers used were polybutyrene succinate (PBS) and polylactic acid (PLA). Two types of silver-based antibacterial agents, silver-based zeolite (AgZL) and silver-based zirconium phosphate (AgZR), were used. The experimental results show that the value of the weight-average molecular weight (Mw), which greatly affects the spinnability of the fiber sample, decreases with the increase in the contents of AgZL and AgZR for both PLA and PBS. The degree of the decrease in the Mw for AgZL was greater than that for AgZR because of the higher content of crystal water for AgZL. The value of antibacterial activity (R) for PLA was higher than that for PBS because of the lactic acid of PLA. AgZL was more effective in terms of antibacterial activity than AgZR in PLA and PBS fiber samples because the elution concentration of silver ions of AgZL is higher than that of AgZR from the initial stage of elution. The biodegradability of PLA and PBS increases with the increase in the content of the antibacterial agent. Especially, the hydrolysis of PLA is accelerated by the silver-based antibacterial agent. Finally, the value of R decreases as the number of washing cycles increases because the antibacterial agent falls of from the polymer surface.

The purpose of this study is to develop recyclable fibrous marine materials. To produce polyethylene fibers protected from breeding of seaweed, copper compound, Cu2O and Cu were mixed with polyethylene in the melt spinning process. The melt spinnabity, the mechanical properties of fibers and the elusion properties of copper ion from fiber were examined. Moreover, the chinning test textile made of molded fibers was carried out in the sea. The highest weight fraction of copper compounds to allow a good melt spinnabity was 25% for Cu2O and 30% for Cu, respectively. However, Cu2O was more effective antifouling material against the seaweed compared with Cu. It is due to the larger amount of copper ion eluted.

An environmentally benign and inexpensive preparation method is described of some imidoyl chlorides, including the Vilsmeier reagent (VR), by using phthaloyl dichloride. Synthetic applications were demonstrated using the isolated VR or VR prepared in situ for the transformation of acids to acid chlorides, alcohols to chlorides, and the formylation of dimethylaminobenzene.

In 1989, Pyriminobac-methyl (Code KIH-6127:Fig. 1, 1) was found to beparticularly effective against barnyard grass (Echinochloa spp.) over a wide range or growth stages from pre-emergence through to the 4.0. leaf stage, with excellent crop safity in both direct-seeded and transplanted rice. It was registered in late 1996 in Japanese as an active ingredient of the one-shot mixture herbicide, Prosper sup (TM) (registered trade name or Kumiai Chemical) and was commercially launched in early 1997, followed soon after by the commercialization or mixtures such as Pat-ful, ASat-ful and Topgun which all contain this com-pound as an active ingredient. Sulfonylurea herbicides like bensulfuron-methyl and pyrazosulfuro-ethyl control sedge and broad-leaf weeds at very low application rates in transplanted rice. These herbicides, however, have only moderate levels of activity against barnyard grass, the most problematic weed in paddy rice, at practical application rates. Since ALS (plant enzyme: acetolactate synthase) inhib-ltory low-dose herbicides including sulfonylurea were not commercially available for the control of barnyard-grass when our studies were initiated, we focused on low-dose herbicides particularly those effective in controlling barnyardgrass in paddy fields. Studies of pyrimidinyl salicylates (Fig. 1, 2) bearing common functional groups, which act by inhibiting ALS, had already been made by the authors. Although most of the compounds had good herbicidal activity, only a few had a broad spectrum of activity and acceptable level of crop safety for commercial use. Therefore, a study of 6-substituted compounds (Fig. 1, 2) was initiated. For the preparation of a variety of 6-substitutions, certain key synthetic intermediates containing a highly reactive functional group linked to the 6-position of the salicylate moiety were required. Our previous studies of 2 had provided the following findings: substitution at the 6-position of the salicylate moiety was preferable for herbicidal and ALS inhibitory

Sodium hypochlorite pentahydrate containing less free sodium hydroxide and sodium chloride oxidizes primary and secondary alcohols to the corresponding aldehydes and ketones in the presence of TEMPO and Bu4NHSO4.

Syntheses of 1,3-difluorobenzene and 2,6-difluorotoluene are described via chlorosulfonation, catalytic Halex-fluorination, and desulfination of 1,3-dichlorobenzene and 2,6-dichlorotoluene.

Ortho-substituted fluorine in 2,4-difluorobenzoic acid was found to be regio-selectively replaced to hydroxide by solid sodium hydroxide in 1,3-dimethyl-2-imidazolidinone, to afford 4-fluoro-2-hydroxybenzoic acid in high yield. Several multi-fluoro-substituted benzoic acid derivatives were effectively transformed to the corresponding salicylic acid derivatives under the similar conditions.

A novel method for the synthesis of Vilsmeier reagent (II) and related imidoyl chlorides uses OPC as chlorinating agent.

A new and efficient synthesis of the title compound is reported. The method includes a regioselective ortho-lithiation step in none polar solvents at an ambient temperature and the overall yield for 5 steps is more than 70% from a commercially available 3-hydroxyacetophenone.

Manganese fluorinated porphyrins catalyzed the ring hydroxylation of phenylalanine derivatives and toluene with H2O2 and an enhanced hydroxylation was observed especially in phospholipid bilayers when imidazole was present. The hydroxylation depended upon the structures of porphyrins and substrates.

3,4-Difluorobenzonitrile has been prepared by a halogen- exchange reaction between 3,4-dichlorobenzonitrile and spray- dried potassium fluoride in the presence of tetraphenylphosphonium bromide in refluxing 1,3-dimethylimidazolidine-2- one. In the fluorination reaction, 4-chloro-3-fluorobenzonitrile seems to be a key intermediate. 3,4-Difluorobenzonitrile, 2-, 3-, and 4-fluorobenzonitriles have also been produced from the corresponding chlorobenzonitrile derivatives by halogen-exchange at 290 °C in DMI in a pressure reactor.

The reaction of chlorobenzoic acid esters with potassium fluoride in the presence of thermally stable phase-transfer catalysts was investigated. The yields of fluorinated products strongly depended on the structure of the substrates employed.

Halogen exchange of 1,2,4,5-tetrachlorobenzene with spray-dried potassium fluoride has been found to proceed smoothly using 1,3-dimethyl-2-imidazol- idinone as a solvent at 300 °C in a pressure reactor to give 2,4,5-tri- fluorochlorobenzene without any rearrangement.