Transition‐metal‐catalyzed multi‐component carbonylation represents an efficient strategy for the preparation of various functionalized carbonyl‐containing compounds. Herein, we report a general ...palladium‐catalyzed perfluoroalkylative carbonylation of unactivated alkenes using inexpensive and readily available carbon monoxide as the C1 source and perfluoroalkyl halides as the coupling partner. A wide range of phenols and alcohols were transformed into the corresponding β‐perfluoroalkyl esters in high yields with broad functional group tolerance and good chemoselectivity. Additionally, alkyl halides can be utilized as alkoxy source as well to give the desired esters. Moreover, several pharmaceutical and bio‐active molecules were also suitable substrates for this one‐pot multi‐component carbonylation process to give the targeted products in good yields.
An efficient and convenient palladium‐catalyzed perfluoroalkylative carbonylation of unactivated alkenes has been developed. More than 100 examples of β‐perfluoroalkyl esters were prepared directly from readily available substrates with good functional group tolerance and chemoselectivity.
Cadmium is a non-essential trace metal that has strong teratogenic and mutagenic effects in living organisms. The content is more highly enriched in women than in men and can enter the embryo through ...the placenta and destroy the placenta's morphological structure, resulting in fetal growth restriction. In this report, we review published data linking pregnancy exposure to cadmium to placenta and fetal growth and development toxicity and summarize the related mechanisms. An understanding of how cadmium exposure contributes to placental and fetal development is necessary for the development of prevention and control strategies for fetal development defects caused by cadmium exposure during pregnancy.
Transition‐metal‐catalyzed multicomponent carbonylation is one of the most efficient strategies to construct carbonyl‐containing compounds. Herein, a palladium‐catalyzed four‐component ...perfluoroalkylation/aminocarbonylation of unactivated alkenes with perfluoroalkyl halides, and amines was developed. A wide range of substrates, including anilines, alkylamines, sulfonamides, and hydrazines are all suitable reaction partners for this catalyst system, resulting in various β‐perfluoroalkyl amides with good functional‐group tolerance and excellent chemoselectivity. Furthermore, not only alkyl olefins, but also aliphatic alkynes, and even alkyl allenes can all be employed. Notably, several medical and bioactive related molecules are compatible here as well.
A convenient and efficient Pd‐catalyzed four‐component perfluoroalkylation/aminocarbonylation strategy for accessing β‐perfluoroalkyl amides has been developed. A wide range of readily available substrates including amines (anilines, alkylamines, sulfonamide, sulfonyl hydrazide, hydrazine, and hydrazides), perfluoroalkyl halides, and unsaturated C−C bonds (alkyl olefins, alkynes, and alkyl allenes) were transformed into the corresponding β‐perfluoroalkyl amides in moderate to high yields with good chemoselectivity and stereoselectivity.
Carbon monoxide is one of the most important C1 molecules in organic chemistry. Many novel procedures for its conversion have been developed, and some have even been industrialized. In this review, ...we discuss and categorize CO chemistry into four classes: (1) transition-metal-mediated carbonylation, (2) strong-acid-initiated cationic carbonylation, (3) anionic carbonylation, and (4) free-radical carbonylation. Relevant achievements are selected and discussed in detail.
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The term “carbonylation” usually refers to organic reactions that install carbon monoxide (CO) into the parent compound. Since the discovery of CO, our understanding of the molecule has evolved greatly, from initial fear regarding its toxicity to its widespread and essential applications. Nowadays, from heating to cooking and from cosmetics to fuels, CO and its related chemistry have become a part of our daily lives. Because of its electronic structure, CO engages in four main types of reactivity that can be used for CO capture: transition-metal catalysis and radical, cation, and anion chemistry. Among the various achievements using these four techniques, in this review we select a few representative examples for discussion and try to inspire a rethink of carbonylation chemistry.
This review provides a different perspective about CO and its chemistry by introducing the possibilities to activate CO by transition-metal catalysts, radicals, cations, and anions. Representative examples have been selected and discussed.
Herein, we have developed a copper-catalyzed hydroaminocarbonylation of benzylidenecyclopropanes under relatively mild conditions. A series of γ,δ-unsaturated amides with a broad range of functional ...groups were obtained in moderate to good yields. Both dialkyl-substituted and monoalkyl-substituted hydroxylamine derivatives can be applied in this transformation to give the corresponding tertiary and secondary amides successfully.
Herein, we have developed a copper-catalyzed hydroaminocarbonylation of benzylidenecyclopropanes under relatively mild conditions.
This paper addresses the problem of computing fixed-interval smoothed state estimates of a linear time varying Gaussian stochastic system. There already exist many algorithms that perform this ...computation, but all of them impose certain restrictions on system matrices in order for them to be applicable, and the restrictions vary considerably between the various existing algorithms. This paper establishes a new sufficient condition for the fixed-interval smoothing density to exist in a Gaussian form that can be completely characterised by associated means and covariances. It then develops an algorithm to compute these means and covariances with no further assumptions required. This results in an algorithm more generally applicable than any one of the multitude of existing algorithms available to date.
Lipophilic marine toxins in shellfish pose significant threats to the health of seafood consumers. To assess the contamination status of shellfish by lipophilic marine toxins in the Bohai Sea, nine ...species of shellfish periodically collected from five representative aquaculture zones throughout a year were analyzed with a method of liquid chromatography-tandem mass spectrometry (LC–MS/MS). Lipophilic marine toxins, including okadaic acid (OA), dinophysistoxin-1 (DTX1), pectenotoxin-2 (PTX2), yessotoxin (YTX), homo-yessotoxin (homo-YTX), azaspiracids (AZA2 and AZA3), gymnodimine (GYM), and 13-desmethyl spirolide C (13-DesMe-C), were detected in more than 95 percent of the shellfish samples. Toxins PTX2, YTX, 13-DesMe-C and GYM were predominant components detected in shellfish samples. Scallops, clams and mussels accumulated much higher level of lipophilic marine toxins compared to oysters. Toxin content in shellfish samples collected from different sampling locations showed site-specific seasonal variation patterns. High level of toxins was found during the stages from December to February and June to July in Hangu, while from March to April and August to September in Laishan. Some toxic algae, including Dinophysis acuminata, D. fortii, Prorocentrum lima, Gonyaulax spinifera and Lingulodinium polyedrum, were identified as potential origins of lipophilic marine toxins in the Bohai Sea. The results will offer a sound basis for monitoring marine toxins and protecting the health of seafood consumers.
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•Shellfish samples were monthly collected from aquaculture zones in the Bohai Sea.•Lipophilic phycotoxins in shellfish were analyzed using HPLC-MS/MS combined with SPE.•Lipophilic phycotoxins could be detected in 104 out of 110 shellfish samples.•PTX2, YTX, SPX1 and GYM were predominated in shellfish samples from the Bohai Sea.•Scallop, clam and mussel were easily contaminated by lipophilic phycotoxins.
A wide array of lipophilic marine toxins were detected in shellfish samples from the Bohai Sea, which constitute an emerging pollution issue in this region.
Cyclopropane represents one of the most critical rings and has been found present in various bioactive compounds, especially in clinical medicines. It can be synthesized by the reaction of olefins ...with diazo-derived carbenoids which are potentially hazardous. Carbonylation is a powerful tool for synthesizing carbonylated or carbon-extended compounds. In this communication, we describe a straightforward approach for synthesizing β-boryl cyclopropane derivatives catalyzed by an inexpensive copper catalyst with CO as the C1 source. This reaction was mediated by an
generated carbene intermediate and afforded a wide range of cyclopropane-containing organoboron compounds in moderate to good yields.
The Yellow Sea (YS) has been subjected to harmful algal blooms (HABs) for several decades. In this study, we compiled and analyzed a dataset of 165 red tides from 1972 to 2017 and a dataset of green ...tides from 2008 to 2017 in the YS. The most notable feature of red tides in the YS is the increasing dominance of dinoflagellate red tides in terms of frequency, scale, seasonal distribution, spatial coverage, and red tide causative species. The increasing dominance of dinoflagellate red tides is closely related to eutrophication and the development of the mariculture industry in the YS. However, the dinoflagellate red tides in the northern Yellow Sea (NYS) and the southern Yellow Sea (SYS) have different features. The apparent changes in red tides in the SYS in terms of frequency and seasonal patterns might have been caused by recurrent large-scale green tides in the last decade.
•Datasets of red tides and green tides recorded in Yellow Sea (YS) were analyzed.•Dominance of dinoflagellate red tides increased in YS after 2000.•Dinoflagellate red tides in northern and southern YS exhibited different features.•Dinoflagellate red tides in YS were related to mariculture and eutrophication.•Red tides in southern YS might be affected by recurrent green tides.
Hydroformylation catalyzed by transition metals is one of the most important homogeneously catalyzed reactions in industrial organic chemistry. Millions of tons of aldehydes and related chemicals are ...produced by this transformation annually. However, most of the applied procedures use rhodium catalysts. In the procedure described here, a copper-catalyzed hydroformylation of alkenes has been realized. Remarkably, by using a different copper precursor, the aldehydes obtained can be further hydrogenated to give the corresponding alcohols under the same conditions, formally named as hydroxymethylation of alkenes. Under pressure of syngas, various aldehydes and alcohols can be produced from alkenes with copper as the only catalyst, in excellent regioselectivity. Additionally, an all-carbon quaternary center containing ethers and formates can be synthesized as well with the addition of unactivated alkyl halides. A possible reaction pathway is proposed based on our results.
A copper-catalyzed hydroformylation and hydroxymethylation of alkenes has been realized.
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