Cu(I)/TF-BiphamPhos-catalyzed asymmetric Michael addition of cyclic ketimino esters to alkylidene malonates.

Cu(I)-catalyzed asymmetric Michael addition of cyclic ketimino esters with alkylidene malonates has been developed for efficient construction of ß-branched α-amino acids containing adjacent quaternary and tertiary stereogenic centers in good yields with excellent diastereo-/enantioselectivities. The generated Michael adduct was further converted to the biologically important pyrrolizidine analogues via one-pot sequential reduction/lactamization.

1,1,1,3,3,3-Hexafluoro-2-propanol (HFIP)-Assisted Catalyst-Free Sulfonation of Allylic Alcohols with Sulfinyl Amides.

A highly regioselective and catalyst-free sulfonation of allylic alcohols with sulfinyl amides has been realized. Such a mix-and-go procedure provides a convenient approach to synthetically various allylic sulfones under mild reaction conditions. Furthermore, this novel reaction shows ample substrate scope and outstanding functional group tolerance and could also be scaled-up. Meanwhile, it is the first example that sulfinyl amides act as a powerful sulfur nucleophile in the reactions. 1,1,1,3,3,3-Hexafluoro-2-propanol (HFIP) as a solvent plays a critical role in allylic sulfonation.

A facile Cu(I)/TF-BiphamPhos-catalyzed asymmetric approach to unnatural α-amino acid derivatives containing gem-bisphosphonates.

A novel catalytic asymmetric Michael addition of azomethine ylide with ß-substituted alkylidene bisphosphates was realized in the presence of a chiral copper(I)/TF-BiphamPhos complex. The present system provides a unique and facile access to enantioenriched unnatural α-amino acid derivatives containing gem-bisphosphonates (gem-BPs) in high yields with excellent diastereoselectivities and enantioselectivities. Subsequent transformations lead to the expedient preparation of biologically active unnatural α-amino acid derivatives containing BPs and bisphosphonic acids without loss of diastereo- and enantiomeric excess.

Asymmetric construction of 3-vinylidene-pyrrolidine derivatives containing allene moiety via Ag(I)/TF-BiphamPhos-catalyzed 1,3-dipolar cycloaddition of azomethine ylides with diethyl 2-(3,3-diphenylpropa-1,2-dienylidene) malonate.

Catalytic asymmetric 1,3-dipolar cycloaddition of various azomethine ylides with diethyl 2-(3,3-diphenylpropa-1,2-dienylidene)malonate has been developed successfully with good to excellent enantioselectivity for the effcient construction of 3-vinylidene-pyrrolidine derivatives containing a unique allene moiety.

Catalytic asymmetric 1,3-dipolar cycloaddition of N-unprotected 2-oxoindolin-3-ylidene derivatives and azomethine ylides for the construction of spirooxindole-pyrrolidines.

Asymmetric 1,3-dipolar cycloaddition of N-unprotected 2-oxoindolin-3-ylidene with azomethine ylides for the construction of spirooxindole-pyrrolidines bearing four contiguous stereogenic centers has been achieved with AgOAc/TF-BiphamPhos complexes for the first time. This catalytic system performance well over a broad scope of substrates, providing the synthetically useful adducts in high yields and excellent diastereoselectivities and moderate enantioselectivities.

Highly enantioselective 1,3-dipolar cycloaddition of azomethine ylides catalyzed by AgOAc/TF-BiphamPhos.

A novel and highly efficient AgOAc/TF-BiphamPhos catalytic system shows excellent reactivity, diastereo-/enantioselectivity and structural scope in asymmetric 1,3-dipolar cycloaddition of azomethine ylides, especially derived from various alpha-substituted alpha-amino acids, with N-substituted maleimides and other electron-deficient alkenes.

Highly enantioselective 1,3-dipolar cycloaddition of azomethine ylides catalyzed by copper(I)/TF-BiphamPhos complexes.

A new and highly efficient Cu(I)/TF-BiphamPhos catalytic system exhibited excellent reactivity, enantio-/diastereoselectivity, and structural scope in asymmetric 1,3-dipolar cycloaddition of azomethine ylides with 0.1-3 mol % of catalyst loading. The present methodology is the best result for asymmetric cycloaddition of azomethine ylides, especially derived from amino esters other than glycinate in terms of reactivity and enantioselectivity.

Highly anti-selective asymmetric nitro-mannich reactions catalyzed by bifunctional amine-thiourea-bearing multiple hydrogen-bonding donors.

Highly anti-selective and enantioselective nitro-Mannich reactions have been achieved for a broad spectrum of substrates catalyzed by chiral bifunctional multiple hydrogen-bonding-donor amine-thioureas. Multiple hydrogen-bonding donors play a significant role in accelerating reactions and improving yields, diastereoselectivities, and enantioselectivities.

Silver(I)-Catalyzed Enantioselective Desymmetrization of Cyclopentenediones: Access to Highly Functionalized Bicyclic Pyrrolidines.

A highly enantioselective desymmetrization of prochiral cyclopentenediones via Ag(I)-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylide has been developed successfully. The methodology performs well over a broad scope of substrates, which provides facile access to a series of highly functionalized bicyclic pyrrolidine/cyclopentane derivatives in good to high yields with excellent stereoselectivities.

Housefly maggot-treated composting as sustainable option for pig manure management.

In traditional composting, large amounts of bulking agents must be added to reduce the moisture of pig manure, which increases the cost of composting and dilutes the N, P and K content in organic fertilizers. In this study, maggot treatment was used in composting instead of bulking agents. In experiment of selecting an optimal inoculum level for composting, the treatment of 0.5% maggot inoculum resulted in the maximum yield of late instar maggots, 11.6% (maggots weight/manure weight). The manure residue became noticeably granular by day 6 and its moisture content was below 60%, which was suitable for further composting without bulking agents. Moreover, in composting experiment with a natural compost without maggot inoculum and maggot-treated compost at 0.5% inoculum level, there were no significant differences in nutrient content between the two organic fertilizers from the two treatments (paired Student's t15=1.0032, P=0.3317). Therefore, maggot culturing did not affect the characteristics of the organic fertilizer. The content of TNPK (total nitrogen+total phosphorus+total potassium) in organic fertilizer from maggot treatment was 10.72% (dry weight), which was far more than that of organic fertilizer made by conventional composting with bulking agents (about 8.0%). Dried maggots as feed meet the national standard (GB/T19164-2003) for commercial fish meal in China, which contained 55.32 ± 1.09% protein; 1.34 ± 0.02% methionine; 4.15 ± 0.10% lysine. This study highlights housefly maggot-treated composting can be considered sustainable alternatives for pig manure management to achieve high-quality organic fertilizer and maggots as feed without bulking agents.

Rapid production of maggots as feed supplement and organic fertilizer by the two-stage composting of pig manure.

A two-stage composting experiment was performed to utilize pig manure for producing maggots as feed supplement and organic fertilizer. Seven-day composting of 1.8 ton fresh manure inoculated with 9 kg mixture of housefly neonates and wheat bran produced 193 kg aging maggots, followed by 12 week composting to maturity. Reaching the thermophilic phase and final maturity faster was characteristic of the maggot-treated compost compared with the same-size natural compost. Upon the transit of the maggot-treated compost to the second stage, the composting temperature maintained around 55 °C for 9 days and the moisture decreased to ~40%. Moreover, higher pH, faster detoxification and different activity patterns for some microbial enzymes were observed. There was a strong material loss (35% water-soluble carbon and 16% total nitrogen) caused by the maggot culture in the first stage. Our results highlight a higher economic value of pig manure achieved through the two-stage composting without bulking agents.

[Effect of aeration intensity on the nitrogen and phosphorus removal performance of AOA membrane bioreactors].

The ability of simultaneous phosphorus and nitrogen removal of sequencing batch membrane bioreactor run in anaerobic/oxic/ anoxic mode (AOA MBR) was examined under three aeration intensities [2.5, 3.75 and 5.0 m3 x (m2 x h)(-10]. The results showed that the averaged removals of COD were over 90% at different aeration intensities. And the higher aeration intensity was, the more ammonia nitrogen removal rate achieved. The removal rates of NH4(+) under the three aeration intensities were 84.7%, 90.6% and 93.8%, respectively. Total nitrogen removal rate increased with the increasing aeration intensity. But excessive aeration intensity reduced TN removal. The removal rates of TN under the three aeration intensities were 83.4%, 87.4% and 80.6%, respectively. Aeration intensity affected the denitrifying phosphorus ability of the AOA MBR. The ratio of denitrification phosphorus removal under the three aeration intensities were 20%, 30.2% and 26.7%, respectively.

[Study on the degradation of AO7 by UV/K2S2O8, system: kinetics and pathways].

The UV photolysis of S2O8(2-) is a novel advanced oxidation technologies (AOTs), which leads to the formation of strong oxidizing radicals, sulfate radicals (SO4(*-)). The effect of oxidant K2S2O8 concentration, the initial pH of solution and various inorganic anions (H2PO4-, HCO3-, NO3- and Cl-) were investigated using AO7, a kind of azo dye, as a model pollutant. The degradation kinetics of AO7 followed pseudo first-order kinetics and reaction rates related to PMS concentrations. When the initial concentration of AO7 was 0.14 mmol/L, the optimal molar ratio of oxidant K2S2O8 to pollutants AO7 was 20. The effect of initial pH had great effect on the AO7 degradation rate during UV/K2S2O8 system. Increasing system pH results in the formation of *OH from SO4(*-). The effects of four inorganic anions (H2PO4-, HCO3-, NO3- and Cl-) all had some negative effect on the degradation of AO7. Based on the results of GC/MS, three main intermediates (2-naphthalenol, coumarin and 1,2-benzenedicarboxylic acid) were identified, thus the degradation pathway for SO4(*-) induced by UV/K2S2O8 was proposed accordingly.

exo-Selective asymmetric 1,3-dipolar cycloaddition of azomethine ylides with alkylidene malonates catalyzed by AgOAc/TF-BiphamPhos.

The first exo-selective asymmetric 1,3-dipolar cycloaddition of alkylidene malonates with azomethine ylides catalyzed by AgOAc/TF-BiphamPhos has been reported in good yields and good to excellent enantio-/diastereoselectivities.