Rethinking the Gains from Immigration: Theory and Evidence from the U.S.

Recent influential empirical work has emphasized the negative impact immigrants have on the wages of U.S.-born workers, arguing that immigration harms less educated American workers in particular and all U.S.-born workers in general. Because U.S. and foreign born workers belong to different skill groups that are imperfectly substitutable, one needs to articulate a production function that aggregates different types of labor (and accounts for complementarity and substitution effects) in order to calculate the various effects of immigrant labor on U.S.-born labor. We introduce such a production function, making the crucial assumption that U.S. and foreign-born workers with similar education and experience levels may nevertheless be imperfectly substitutable, and allowing for endogenous capital accumulation. This function successfully accounts for the negative impact of the relative skill levels of immigrants on the relative wages of U.S. workers. However, contrary to the findings of previous literature, overall immigration generates a large positive effect on the average wages of U.S.-born workers. We show evidence of this positive effect by estimating the impact of immigration on both average wages and housing values across U.S. metropolitan areas (1970-2000). We also reproduce this positive effect by simulating the behavior of average wages and housing prices in an open city-economy, with optimizing U.S.-born agents who respond to an inflow of foreign-born workers of the size and composition comparable to the immigration of the 1990s

Scalable and Safe Transformation of 3‑Hydroxypropionitrile to Its Amidoxime

Scalable synthesis of amidoxime 1 by nucleophilic addition of 50% aq. NH2OH to 3-hydroxypropionitrile is reported. In the presence of hydroxyl and amidoxime moieties, this dually functional compound can be manipulated for the synthesis of heterocyclic compounds that may be useful for the energetic materials and pharmaceutical chemistry communities. In preparing 1, it was discovered that previously published procedures were either irreproducible and/or the processes were not practical on larger scales. Previously published procedures required flash chromatography and/or afforded the amidoxime product in a low yield. The improved method discussed in this paper involves rotary evaporation of the completed reaction mixture to remove excess water, followed by trituration in acetone to obtain 83–90% yields. This method has been carried out multiple times on the 86–94 g scale, with minimal exothermic activity detected

Photochemical Strategies Enable the Synthesis of Tunable Azetidine-Based Energetic Materials

Despite their favorable properties, azetidines are often overlooked as lead compounds across multiple industries. This is often attributed to the challenging synthesis of densely functionalized azetidines in an efficient manner. In this work, we report the scalable synthesis and characterization of seven azetidines with varying regio- and stereochemistry, and their application as novel azetidine-based energetic materials, enabled by the visible light-mediated aza Paternò-Büchi reaction. The performance and stark differences in physical properties of these new compounds make them excellent potential candidates as novel solid melt-castable explosive materials, as well as potential liquid propellant plasticizers. The nitroazetidine materials synthesized exhibit reasonable sensitivities, higher densities, better oxygen balances, increased detonation pressures and velocities, as well as improved specific impulses, compared to the state-of-the-art materials. This work highlights the scalability and utility of the visible-light aza Paternò-Büchi reaction and demonstrates the impact of stereochemical considerations on the physical properties of azetidine-based energetics. Considering the versatility and efficiency of the presented synthetic strategies, we expect that this work will guide the development of new azetidine-based materials in the energetics space as well as other industries, including pharmaceuticals and agrochemicals.</jats:p

Photochemical Strategies Enable the Synthesis of Tunable Azetidine-Based Energetic Materials

Despite their favorable properties, azetidines are often overlooked as lead compounds across multiple industries. This is often attributed to the challenging synthesis of densely functionalized azetidines in an efficient manner. In this work, we report the scalable synthesis and characterization of seven azetidines with varying regio- and stereochemistry, and their application as novel azetidine-based energetic materials, enabled by the visible light-mediated aza Paternò-Büchi reaction. The performance and stark differences in physical properties of these new compounds make them excellent potential candidates as novel solid melt-castable explosive materials, as well as potential liquid propellant plasticizers. The nitroazetidine materials synthesized exhibit reasonable sensitivities, higher densities, better oxygen balances, increased detonation pressures and velocities, as well as improved specific impulses, compared to the state-of-the-art materials. This work highlights the scalability and utility of the visible-light aza Paternò-Büchi reaction and demonstrates the impact of stereochemical considerations on the physical properties of azetidine-based energetics. Considering the versatility and efficiency of the presented synthetic strategies, we expect that this work will guide the development of new azetidine-based materials in the energetics space as well as other industries, including pharmaceuticals and agrochemicals

A Safer Synthesis of the Explosive Precursors 4‑Aminofurazan-3-Carboxylic Acid and its Ethyl Ester Derivative

A safe and efficient one-pot synthesis of 4-aminofurazan-3-carboxylic acid and its hydrogen chloride gas-free conversion to the ethyl ester derivative are described. Previous syntheses of these intermediates were plagued with mischaracterization issues, low yields, and/or dangerous exothermic profiles. The safe scale-up of these materials not only provides benefits to the energetic materials community but may also be of importance to the pharmaceutical and agrochemicals industries