Actuarial Model Assumptions for Australian Inflation, Equity Returns, and Interest Rates

Though actuaries have developed several types of stochastic investment models for inflation, stock market returns, and interest rates, there are two commonly used in practice: autoregressive time series models with normally distributed errors, and autoregressive conditional heteroscedasticity (ARCH) models. ARCH models are particularly suited when there is heteroscedasticity in inflation and interest rate series. In such cases nonnormal residuals are found in the empirical data. This paper examines whether Australian univariate inflation and interest rate data are consistent with autoregressive time series and ARCH model assumptions

Rh-Catalyzed Decarbonylative Coupling with Alkynes via C–C Activation of Isatins

Herein we report a [5 + 2 – 1] transformation though catalytic decarbonylative coupling between isatins and alkynes, which provides a unique way to synthesize 2-quinolinone derivatives. A broad range of alkynes can be coupled efficiently with high regioselectivity. This reaction is proposed to go through C–C activation of isatins, followed by decarbonylation and alkyne insertion. Directing group (DG) plays a critical role in this transformation. Assisted by the DG, the C–C cleavage of isatins occurs at room temperature

Highly Selective Mild Stepwise Allylation of <i>N</i>-Methoxybenzamides with Allenes

An efficient Rh­(III)-catalyzed stepwise ortho allylation of <i>N</i>-methoxybenzamides <b>1</b> with polysubstituted allenes is reported. This C–H functionalization involving allenes is conducted under very mild conditions (−20 °C or room temperature) and compatible with ambient air and moisture, and it can be applied to terminal or internal allenes with different synthetically attractive functional groups. Highly efficient axial chirality transfer has been realized, yielding optically active lactones

Efficient Benzimidazolidinone Synthesis via Rhodium-Catalyzed Double-Decarbonylative C–C Activation/Cycloaddition between Isatins and Isocyanates

The first decarbonylative cycloaddition of less-strained cyclic ketones (isatins) with isocyanates is reported. Initiated by C–C activation, this distinct [5 – 2 + 2] transformation provides a rapid entry to access various benzimidazolidinone derivatives, and a wide range of isocyanates can be efficiently coupled with broad functional group tolerance. A modified one-pot process combining a Curtius rearrangement and C–C activation was also achieved by using acyl azides as the starting materials. A detailed mechanistic study revealed a surprising double-decarbonylative reaction pathway. The novel reactivity discovered in this basic research is expected to shed light on the development of new heterocycle formation methods through C–C/isocyanate coupling

Efficient Benzimidazolidinone Synthesis via Rhodium-Catalyzed Double-Decarbonylative C–C Activation/Cycloaddition between Isatins and Isocyanates

The first decarbonylative cycloaddition of less-strained cyclic ketones (isatins) with isocyanates is reported. Initiated by C–C activation, this distinct [5 – 2 + 2] transformation provides a rapid entry to access various benzimidazolidinone derivatives, and a wide range of isocyanates can be efficiently coupled with broad functional group tolerance. A modified one-pot process combining a Curtius rearrangement and C–C activation was also achieved by using acyl azides as the starting materials. A detailed mechanistic study revealed a surprising double-decarbonylative reaction pathway. The novel reactivity discovered in this basic research is expected to shed light on the development of new heterocycle formation methods through C–C/isocyanate coupling

Efficient Benzimidazolidinone Synthesis via Rhodium-Catalyzed Double-Decarbonylative C–C Activation/Cycloaddition between Isatins and Isocyanates

The first decarbonylative cycloaddition of less-strained cyclic ketones (isatins) with isocyanates is reported. Initiated by C–C activation, this distinct [5 – 2 + 2] transformation provides a rapid entry to access various benzimidazolidinone derivatives, and a wide range of isocyanates can be efficiently coupled with broad functional group tolerance. A modified one-pot process combining a Curtius rearrangement and C–C activation was also achieved by using acyl azides as the starting materials. A detailed mechanistic study revealed a surprising double-decarbonylative reaction pathway. The novel reactivity discovered in this basic research is expected to shed light on the development of new heterocycle formation methods through C–C/isocyanate coupling

Room-Temperature Synthesis of Trisubstituted Allenylsilanes via Regioselective C–H Functionalization

A Rh­(III)-catalyzed <i>o</i>-C–H bond functionalization-based allenyl­ation reaction of allenyl­silanes <b>2</b> with <i>N</i>-methoxy­benz­amides <b>1</b> affords poly-substituted allenyl­silanes with a wide range of attractive functional groups in moderate to excellent yields under very mild conditions (20 °C, compatible with ambient air and moisture). Those products may be transformed to different products with attractive structural features. Careful mechanistic studies suggest the reaction proceeds via <i>o</i>-rhodation, regioselective insertion, and β-H elimination

Room-Temperature Synthesis of Trisubstituted Allenylsilanes via Regioselective C–H Functionalization

A Rh­(III)-catalyzed <i>o</i>-C–H bond functionalization-based allenyl­ation reaction of allenyl­silanes <b>2</b> with <i>N</i>-methoxy­benz­amides <b>1</b> affords poly-substituted allenyl­silanes with a wide range of attractive functional groups in moderate to excellent yields under very mild conditions (20 °C, compatible with ambient air and moisture). Those products may be transformed to different products with attractive structural features. Careful mechanistic studies suggest the reaction proceeds via <i>o</i>-rhodation, regioselective insertion, and β-H elimination

Hydrogenation and Hydrosilylation of Nitrous Oxide Homogeneously Catalyzed by a Metal Complex

Due to its significant contribution to stratospheric ozone depletion and its potent greenhouse effect, nitrous oxide has stimulated much research interest regarding its reactivity modes and its transformations, which can lead to its abatement. We report the <i>homogeneously</i> catalyzed reaction of nitrous oxide (N₂O) with H₂. The reaction is catalyzed by a PNP pincer ruthenium complex, generating efficiently only dinitrogen and water, under mild conditions, thus providing a green, mild methodology for removal of nitrous oxide. The reaction proceeds through a sequence of dihydrogen activation, “O”-atom transfer, and dehydration, in which metal–ligand cooperation plays a central role. This approach was further developed to catalytic O-transfer from N₂O to Si–H bonds

BuildSummary: Using a Group-Based Approach To Improve the Sensitivity of Peptide/Protein Identification in Shotgun Proteomics

The target-decoy database search strategy is widely accepted as a standard method for estimating the false discovery rate (FDR) of peptide identification, based on which peptide-spectrum matches (PSMs) from the target database are filtered. To improve the sensitivity of protein identification given a fixed accuracy (frequently defined by a protein FDR threshold), a postprocessing procedure is often used that integrates results from different peptide search engines that had assayed the same data set. In this work, we show that PSMs that are grouped by the precursor charge, the number of missed internal cleavage sites, the modification state, and the numbers of protease termini and that the proteins grouped by their unique peptide count should be filtered separately according to the given FDR. We also develop an iterative procedure to filter the PSMs and proteins simultaneously, according to the given FDR. Finally, we present a general framework to integrate the results from different peptide search engines using the same FDR threshold. Our method was tested with several shotgun proteomics data sets that were acquired by multiple LC/MS instruments from two different biological samples. The results showed a satisfactory performance. We implemented the method in a user-friendly software package called <i>BuildSummary</i>, which can be downloaded for free from http://www.proteomics.ac.cn/software/proteomicstools/index.htm as part of the software suite <i>ProteomicsTools</i>