The enantioselective functionalization of allylic positions has attracted the attention of organic chemists owing to the broad synthetic potential of the product, functionalized enantio-enriched alkenes.[1] Transition-metal-catalyzed asymmetric allylic alkylation is the most developed strategy in allylic transformations and its popularity is due to its tolerance to a variety of functional groups and its flexibility in diverse bond constructions.[2] However, the conspicuous drawbacks of transition-metal-catalyzed allylic alkylation include the use of toxic and expensive metals and the generation of a stoichiometric amount of waste, the leaving group. To avoid using transition metals, other strategies with chiral allylsilanes, allylboronates, and allylboranes were also developed.[3] Recent improvements include the use of chiral BINOL-derived diols to catalyze the highly enantioselective asymmetric allylboration of ketones.[4] In addition, Lewis acidic indium complexes with low toxicity were found to be efficient catalysts for the asymmetric CÀC bond formations between hydrazones and allyl boronates. [5] Recently, direct allylation reactions using all carbon allylic nucleophiles have attracted considerable attention. For example, the direct asymmetric addition of allyl cyanides or b,g-unsaturated esters to different electrophiles was successful using soft Lewis acid/hard Brønsted base cooperative catalysts.[6] Alternatively, organocatalytic approaches were investigated for the g-functionalization of a,b-unsaturated carbonyl compounds. [7] Addition of alkylidene cyanoacetates to acrolein was reported that utilized cinchona alkaloids as chiral bases.[8] Carbonyl allylation of methyl trifluoropyruvate with activated alkenes by non-chiral organobases was also described.[9] For the above-mentioned examples, strong electron-withdrawing groups were required to activate the olefin to enhance the acidity of the allylic protons. The resulting regioselectivity for either a-or g-addition, depends on the combination of substrates and the catalyst used.Previously, we have successfully demonstrated that N-aryl methylidene-succinimides (N-aryl itaconimides) were good electrophiles in enantioselective protonation reactions.[10] In the transformation, we observed that isomerization of the alkene moiety in these methylidene-succinimides could occur and led to the thermodynamically more stable maleimide derivatives under basic conditions (Figure 1) 2010, 16, 12534 -12537 12534 hypothesized that the a-protons of these methylidene-succinimides were acidic enough to be activated by an organobase. To support this hypothesis, a deuteration-isomerization experiment was designed. A 1:1 mixture of N-(3,5-difluorophenyl)methylidene-succinimide (1 a) and triethylamine was monitored in a solvent mixture of CDCl 3 /D 2 O (3:1) by NMR spectroscopy. Results indicated that both the a-protons and g-protons in methylidene-succinimide 1 a were deuterated under these basic conditions. Further analysis of the isomerization process revealed the existe...

High-quality bio-organic fertilizers (BIOs) cannot be produced without the addition of some proteins. In this study, compound liquid amino acids (CLAA) from animal carcasses were utilized as additives into matured composts to create novel BIOs containing plant growth-promoting rhizobacteria (PGPR). The results showed that adding CLAA and inoculating bacteria meanwhile resulted in failed solid-state fermentation (SSF) due to the higher H+ contents. While after pre-compost for 4 days before PGPR inoculation, treatments of matured chicken or pig manure added with 0.2 ml g-1 of CLAA resulted in a maximum biomass of functional strains. Illumine-MiSeq sequencing and Real-Time PCR results showed that the CLAA addition decreased the bacterial abundance and richness, altered the bacterial community structure and changed the relative abundance of some microbial groups. This study offers a high value-added utilization of waste protein resources for producing economical, high-quality BIO.

An experimental study on the effects of loading cycles on the performance of STF dampers (STFDs) are presented. The rheological properties of a STF sample are investigated under both ascending and descending loads. A smart damper is then developed and manufactured by employing the STF sample. Two series of cyclic tests were conducted to investigate the behaviour of the STFD under various sinusoidal loading conditions with a constant amplitude of 20 mm. Eight different loading frequencies (0.01, 0.1, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 Hz) were imposed to research on the effect of frequency. Three different loading frequencies (1, 2 and 3 Hz) were applied to the STFD under a constant amplitude (20 mm) with long-term loading (200 cycles). The energy dissipation and dynamic properties of STFD were investigated by analysing the force-displacement and force-velocity curves. The STF damping force is found to decay exponentially as the loading cycles increase. An equation is proposed for the description of STFD force at different loading cycles and frequencies.

Hydroisoquinoline derivatives were prepared in moderate to good enantioselectivities via a bicyclic guanidine-catalyzed tandem isomerization intramolecular-Diels-Alder (IMDA) reaction of alkynes. With this synthetic method, the first enantioselective synthesis of (+)-alpha-yohimbine was completed in 9 steps from the IMDA products.

Useful degradation: A highly enantio‐ and diastereoselective guanidine‐catalyzed Mannich reaction was developed with α‐fluoro‐β‐keto acyloxazolidinone as the fluorocarbon nucleophile (see scheme). α‐Fluoro‐β‐amino ester and α‐fluoro‐β‐amino ketones with chiral fluorinated carbon were obtained by selective deacylation and decarboxylation reactions, respectively.

SUMMARY Real‐time hybrid structural testing is a novel method that is gaining acceptance for examination of civil engineering structures. This method facilitates testing of an unknown physical component coupled with an analytical model of the remainder of the structure. A primary challenge in performing real‐time hybrid testing to accurately reproduce the behavior of the complete system is the appropriate compensation of actuator dynamics. Accounting for the magnitude roll‐off while also reducing the time lags to a minimal value is critical to ensure both accuracy and stability of a real‐time hybrid structural test. Here, a new compensation scheme is proposed that integrates the best features of two commonly used approaches. The proposed method, simply called integrated compensation, uses online delay estimation to improve on the performance of inverse compensation method for problems in which the effective time delay is not constant over the frequency band of interest. Two real‐time experiments are conducted to examine the capabilities of the approach for achieving good displacement tracking. Both experiments focus on the use of a device as the physical component. One experiment uses a linear spring as the physical component, and one uses a controllable, nonlinear damping device. The actuator displacement tracking results are compared with the results using other compensation approaches. The results from these experiments demonstrate that the proposed integrated compensation method is very effective and suitable for real‐time hybrid testing using a device as the physical component. Copyright © 2012 John Wiley & Sons, Ltd.

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