Re(CO)₅Br-Catalyzed Addition of Carboxylic Acids to Terminal Alkynes: A High Anti-Markovnikov and Recoverable Homogeneous Catalyst

The addition of carboxylic acids to terminal alkynes is efficiently catalyzed by the early transition-metal complex Re(CO)5Br in toluene or n-heptane at 110 °C in an air atmosphere, affording the anti-Markovnikov adducts in good yields with high selectivity. In most cases, the reactions afford unusual Z-adduct predominantly. When n-heptane was used as solvent, Re(CO)5Br can be partly recovered from the reaction mixture

The Y maze working memory task and preprocessing of the data.

<p>(A) The Y maze working memory task. For the Y maze, dashed lines represent the removable guillotine doors. The occurrence of behavioral event is detected by an infrared sensor. Food rewards are located at the ends of goal arms. Arrow shows in the right plot possible correct path, dotted line in the right plot shows possible incorrect path. (B) Processes of spike sorting. (C) Rastergram of the spike trains recorded during the Y-maze task (3 s pre and 1 s post the tripping time) and the converted continuous series. The red triangle denotes the tripping time of the ‘choice run’ behavioral event in the Y-maze. (D) Plot of the principal components obtained from the continuous time series. The first 10 principal components (PCs) account for over 90% energy of the total variables. (E) Granger causality matrices in the original (left) and in the reduced dimensionality (right).</p

Comparisons of the global efficiency of original and reduced dimensionality at WMBS and WMS^a.

a<p>The values are the mean ± SEM of the global efficiency values of each rats (paired sample <i>t</i> test).</p>b<p>Total number of the compared groups.</p><p>* p<0.05 compared to the global efficiency values at the WMBS in the original dimensionality or the reduced dimensionality.</p><p>** p<0.01 compared to the global efficiency values at the WMBS in the original dimensionality or the reduced dimensionality.</p>▵<p>p<0.05 compared to the global efficiency values of the original dimensionality at the WMBS or at the WMS.</p>▵▵<p>p<0.01 compared to the global efficiency values of the original dimensionality at the WMBS or at the WMS.</p

Dynamic variations of granger causality during working memory tasks.

<p>The data are divided into six 1(4 s pre and 2 s post the tripping time). The red triangle indicates the tripping time of the infrared sensor in the Y-maze. (A) Dynamic variations of the granger causality matrixes during a working memory task of rat 1. (B) Variations of the GC values in the original dimensionality during the working memory tasks of each rat (mean±SEM). (C) Variations of the GC_PC values in the reduced dimensionality during the working memory tasks of each rat (mean±SEM). (D) Comparisons of granger causality (mean±SEM). The granger causality values of the original and the reduced dimensionality are both significantly higher at the working memory state (WMS) than at the beginning state (WMBS). Besides, the granger causality levels in the original dimensionality at the WMS and the WMBS are significantly lower than those in the reduced dimensionality (80 trials for 6 rat, paired sample t-test, ^* P<0.05, ^** P<0.01).</p

Dynamic variations of global efficiency and causal density both in the original and in the reduced dimensionality during working memory tasks, 6 rats respectively.

<p>(A) The dynamic variations of global efficiency in the original dimensionality (dashed lines) and the reduced dimensionality (solid lines) during the WM tasks, 6 rats respectively (mean±SEM). (B) The dynamic variations of causal density in the original dimensionality (dashed lines) and the reduced dimensionality (solid lines) during WM tasks, 6 rats respectively (mean±SEM). The red triangle indicates the tripping time of the infrared sensor in the Y-maze. (C) Comparisons of global efficiency (mean±SEM). The values of the global efficiency in both the original and the reduced dimensionality are significantly higher at the WMS than at the WMBS. The E values in the original dimensionality at the WMS are significantly lower than the E_PC values in the reduced dimensionality (80 trials for 6 rat, paired sample t-test, ^** P<0.01). No significant difference is found at the WMBS (80 trials for 6 rat, paired sample t-test, P>0.05). (D) Comparisons of causal density (mean±SEM). The values of the causal density in both the original and the reduced dimensionality are significantly higher at the WMS than at the WMBS. The CD values in the original dimensionality at the WMS are significantly lower than the CD_PC values in the reduced dimensionality (80 trials for 6 rat, paired sample t-test, ^** P<0.01). No significant difference is found at the WMBS (80 trials for 6 rat, paired sample t-test, P>0.05).</p

(β-Diketiminato)palladium Complexes

Reaction of Pd(acac)2 with 1 equiv of the lithium β-diketiminate Li(iPr2-nacnac) (iPr2-nacnac = CH{C(Me)NiPr}2) affords the dark red mixed-ligand complex (acac)Pd(iPr2-nacnac) (1), while with 2 equiv of Li(iPr2-nacnac) the light red homoleptic Pd(iPr2-nacnac)2 (2) is formed. A similar reaction of Pd(acac)2 with the more bulky (THF)Li(Ar2-nacnac) (Ar2-nacnac = CH{C(Me)N(C6H3-2,6-iPr2)}2) proceeds only to the stage of the mixed-ligand complex. While below 0 °C red (acac)Pd(κ2N,N-Ar2-nacnac) (4) is isolated as the kinetically controlled product, which is stable in the solid state, this complex isomerizes in solution at ambient temperature to yield the lighter red and chiral (acac)Pd(κ2C,N-Ar2-nacnac) (5), displaying a novel nacnac bonding mode. The reaction of [Pd(MeCN)4](BF4)2 and that of the Pd(I) complex [Pd2(MeCN)6](BF4)2 with (THF)Li(Ar2-nacnac) gives [(κ2N,N-Ar2-nacnac)Pd(MeCN)2](BF4) (6). The κ2N,N-Ar2-nacnac ligand in 6 is sufficiently nucleophilic to displace acetonitrile from [Pd(MeCN)4](BF4)2 and produce the pure dinuclear [(MeCN)3Pd{μ-CH(C(Me)NAr)2}Pd(MeCN)2](BF4)3 (A), previously accessible only in a mixture. From the reactions of {(η3-C3H5)Pd(μ-Cl)}2 with Li(iPr2-nacnac) and (THF)Li(Ar2-nacnac) the mixed-ligand complexes (η3-C3H5)Pd(iPr2-nacnac) (3a) and (η3-C3H5)Pd(κ2N,N-Ar2-nacnac) (3b) have been obtained. Reaction of (cod)PdMeCl with (THF)Li(Ar2-nacnac) affords (Ar2-nacnac)PdMe(MeCN) (7). An anisotropic effect of the Ar2-nacnac ligand in the 1H NMR spectra of 3b and 4 can be noted. The structures of 2, 3a, 4, and 5 have been determined by X-ray crystallography

Impact of operating rules on planning capacity expansion of urban water supply systems

Water utilities often rely on industrial water supply (e.g. desalination) to complement natural resources. These climate-independent sources of supply allow operators to respond quickly to varying operating conditions, but require them to choose operating strategies, or rules. How does such operational flexibility impact the performance of water supply systems? How might it affect long-term plans for capacity expansion? Possibly significantly, as demonstrated by the analysis of a water supply system based on Singapore. First, we simulate the dynamics of the system under multiple rainfall and operating scenarios to understand the extent to which the operators’ behavior affect system performance. Results show that different operating rules can have comparable impact on the variability in system performance as hydrological conditions. Then, we show that small changes in the operating rules can lead to substantial changes in the capacity expansions, such as the size of a new desalination plant.</p

(β-Diketiminato)palladium Complexes

Reaction of Pd(acac)2 with 1 equiv of the lithium β-diketiminate Li(iPr2-nacnac) (iPr2-nacnac = CH{C(Me)NiPr}2) affords the dark red mixed-ligand complex (acac)Pd(iPr2-nacnac) (1), while with 2 equiv of Li(iPr2-nacnac) the light red homoleptic Pd(iPr2-nacnac)2 (2) is formed. A similar reaction of Pd(acac)2 with the more bulky (THF)Li(Ar2-nacnac) (Ar2-nacnac = CH{C(Me)N(C6H3-2,6-iPr2)}2) proceeds only to the stage of the mixed-ligand complex. While below 0 °C red (acac)Pd(κ2N,N-Ar2-nacnac) (4) is isolated as the kinetically controlled product, which is stable in the solid state, this complex isomerizes in solution at ambient temperature to yield the lighter red and chiral (acac)Pd(κ2C,N-Ar2-nacnac) (5), displaying a novel nacnac bonding mode. The reaction of [Pd(MeCN)4](BF4)2 and that of the Pd(I) complex [Pd2(MeCN)6](BF4)2 with (THF)Li(Ar2-nacnac) gives [(κ2N,N-Ar2-nacnac)Pd(MeCN)2](BF4) (6). The κ2N,N-Ar2-nacnac ligand in 6 is sufficiently nucleophilic to displace acetonitrile from [Pd(MeCN)4](BF4)2 and produce the pure dinuclear [(MeCN)3Pd{μ-CH(C(Me)NAr)2}Pd(MeCN)2](BF4)3 (A), previously accessible only in a mixture. From the reactions of {(η3-C3H5)Pd(μ-Cl)}2 with Li(iPr2-nacnac) and (THF)Li(Ar2-nacnac) the mixed-ligand complexes (η3-C3H5)Pd(iPr2-nacnac) (3a) and (η3-C3H5)Pd(κ2N,N-Ar2-nacnac) (3b) have been obtained. Reaction of (cod)PdMeCl with (THF)Li(Ar2-nacnac) affords (Ar2-nacnac)PdMe(MeCN) (7). An anisotropic effect of the Ar2-nacnac ligand in the 1H NMR spectra of 3b and 4 can be noted. The structures of 2, 3a, 4, and 5 have been determined by X-ray crystallography

(β-Diketiminato)palladium Complexes

Reaction of Pd(acac)2 with 1 equiv of the lithium β-diketiminate Li(iPr2-nacnac) (iPr2-nacnac = CH{C(Me)NiPr}2) affords the dark red mixed-ligand complex (acac)Pd(iPr2-nacnac) (1), while with 2 equiv of Li(iPr2-nacnac) the light red homoleptic Pd(iPr2-nacnac)2 (2) is formed. A similar reaction of Pd(acac)2 with the more bulky (THF)Li(Ar2-nacnac) (Ar2-nacnac = CH{C(Me)N(C6H3-2,6-iPr2)}2) proceeds only to the stage of the mixed-ligand complex. While below 0 °C red (acac)Pd(κ2N,N-Ar2-nacnac) (4) is isolated as the kinetically controlled product, which is stable in the solid state, this complex isomerizes in solution at ambient temperature to yield the lighter red and chiral (acac)Pd(κ2C,N-Ar2-nacnac) (5), displaying a novel nacnac bonding mode. The reaction of [Pd(MeCN)4](BF4)2 and that of the Pd(I) complex [Pd2(MeCN)6](BF4)2 with (THF)Li(Ar2-nacnac) gives [(κ2N,N-Ar2-nacnac)Pd(MeCN)2](BF4) (6). The κ2N,N-Ar2-nacnac ligand in 6 is sufficiently nucleophilic to displace acetonitrile from [Pd(MeCN)4](BF4)2 and produce the pure dinuclear [(MeCN)3Pd{μ-CH(C(Me)NAr)2}Pd(MeCN)2](BF4)3 (A), previously accessible only in a mixture. From the reactions of {(η3-C3H5)Pd(μ-Cl)}2 with Li(iPr2-nacnac) and (THF)Li(Ar2-nacnac) the mixed-ligand complexes (η3-C3H5)Pd(iPr2-nacnac) (3a) and (η3-C3H5)Pd(κ2N,N-Ar2-nacnac) (3b) have been obtained. Reaction of (cod)PdMeCl with (THF)Li(Ar2-nacnac) affords (Ar2-nacnac)PdMe(MeCN) (7). An anisotropic effect of the Ar2-nacnac ligand in the 1H NMR spectra of 3b and 4 can be noted. The structures of 2, 3a, 4, and 5 have been determined by X-ray crystallography

Dynamic variations of granger causality, global efficiency and causal density during the incorrect tasks in both the original and the reduced dimensionality (20 trials for 6 rats).

<p>The data are divided into six 1(4 s pre and 2 s post the tripping time). The red triangle indicates the tripping time of the infrared sensor in the Y-maze. (A) Dynamic variations of the granger causality matrixes during an incorrect trial of rat 1. (B) The variations of granger causality (left), global efficiency (middle) and causal density (right) during the incorrect tasks (20 trials for 6 rats) and the correct trials (80 trials for 6 rats) in the original dimensionality. The feature values in the correct trials are significantly higher 2 s (GC, E, CD) and 1 s (E, CD) pre the tripping time than those in the incorrect trials (t test, ^* P<0.05, ^** P<0.01). No statistical difference is found at the WMBS between the incorrect and the correct trials (t test, P>0.05). (C) The variations of granger causality (left), global efficiency (middle) and causal density (right) during the incorrect tasks (20 trials for 6 rats) and the correct trials (80 trials for 6 rats) in the reduced dimensionality. The feature values in the correct trials are significantly higher 2 s (GC_PC, E_PC, CD_PC) and 1 s (GC_PC, E_PC, CD_PC) pre the tripping time than those in the incorrect trials (t test, ^** P<0.01). In addition, the feature values were significantly higher at the WMBS in the incorrect trials (t test, ^* P<0.05).</p