Tunable Synthesis of Functionalized Cyclohexa-1,3-dienes and 2‑Aminobenzophenones/Benzoate from the Cascade Reactions of Allenic Ketones/Allenoate with Amines and Enones

A TEMPO-dependent tunable synthesis of functionalized cyclohexa-1,3-dienes and 2-aminobenzophenones/benzoate from the one-pot cascade reactions of allenic ketones/allenoate with amines and enones is presented. Mechanistically, the construction of the entitled six-membered carbocycles involves the in situ generation of an enaminone intermediate via the conjugate addition of allenic ketone with amine followed by its catalyst- and base-free [3+3] annulation with enone along with the simultaneous introduction of the valuable amino and carbonyl groups

Tunable Synthesis of Functionalized Cyclohexa-1,3-dienes and 2‑Aminobenzophenones/Benzoate from the Cascade Reactions of Allenic Ketones/Allenoate with Amines and Enones

A TEMPO-dependent tunable synthesis of functionalized cyclohexa-1,3-dienes and 2-aminobenzophenones/benzoate from the one-pot cascade reactions of allenic ketones/allenoate with amines and enones is presented. Mechanistically, the construction of the entitled six-membered carbocycles involves the in situ generation of an enaminone intermediate via the conjugate addition of allenic ketone with amine followed by its catalyst- and base-free [3+3] annulation with enone along with the simultaneous introduction of the valuable amino and carbonyl groups

Rhodium(III)-Catalyzed Redox-Neutral Synthesis of Isoquinolinium Salts via C–H Activation of Imines

Redox-neutral synthesis of isoquinolinium salts via C–H activation of presynthesized or in situ formed imines and coupling with α-diazo ketoesters has been realized, where a zinc salt promotes cyclization as well as provides a counteranion. Under three-component conditions, both ketone and aldehydes are viable arene sources. The coupling of imines with diazo malonates under similar conditions afforded isoquinolin-3-ones as the coupling product

Synthesis of Pyrazolo[5,1‑<i>a</i>]isoindoles and Pyrazolo[5,1‑<i>a</i>]isoindole-3-carboxamides through One-Pot Cascade Reactions of 1‑(2-Bromophenyl)buta-2,3-dien-1-ones with Isocyanide and Hydrazine or Acetohydrazide

A novel and efficient method for the construction of the pyrazolo­[5,1-<i>a</i>]­isoindole scaffold via a one-pot three-component cascade reaction of 1-(2-bromophenyl)­buta-2,3-dien-1-one with hydrazine and isocyanide promoted by a Pd catalyst is described. This cascade process proceeds through initial condensation of the allenic ketone with hydrazine followed by Pd-catalyzed isocyanide insertion into the C–Br bond and intramolecular C–N bond formation. Interestingly, when acetohydrazide was used in place of hydrazine, a more sophisticated procedure involving condensation, isocyanide insertion into C–H and C–Br bonds, deacetylation, and formation of C–C, C–O, and C–N bonds occurred to afford pyrazolo­[5,1-<i>a</i>]­isoindole-3-carboxamides with good efficiency

Rhodium(III)-Catalyzed Redox-Neutral Synthesis of Isoquinolinium Salts via C–H Activation of Imines

Redox-neutral synthesis of isoquinolinium salts via C–H activation of presynthesized or in situ formed imines and coupling with α-diazo ketoesters has been realized, where a zinc salt promotes cyclization as well as provides a counteranion. Under three-component conditions, both ketone and aldehydes are viable arene sources. The coupling of imines with diazo malonates under similar conditions afforded isoquinolin-3-ones as the coupling product

Rh(III)-Catalyzed C–C Coupling of Diverse Arenes and 4‑Acyl-1-sulfonyltriazoles via C–H Activation

4-Acyl-1-sulfonyltriazoles act as versatile carbene reagents in Cp*Rh­(III)-catalyzed ortho-selective coupling with arenes via C–H activation. The coupling led to olefination with possible cyclization, depending on the nature of the arene

Synthesis of 4‑Acylpyrazoles from Saturated Ketones and Hydrazones Featured with Multiple C(sp³)–H Bond Functionalization and C–C Bond Cleavage and Reorganization

In this paper, an efficient and convenient one-pot synthesis of diversely substituted 4-acylpyrazole derivatives via copper-catalyzed one-pot cascade reactions of saturated ketones with hydrazones is reported. Mechanistically, the formation of the title compounds involves the in situ formation of an enone intermediate through the dehydrogenation of a saturated ketone and the [2 + 3] cyclization of the enone with hydrazone followed by an aromatization-driven C–C bond cleavage and reorganization. To our knowledge, this is the first example in which the biologically and pharmaceutically important yet otherwise difficult-to-obtain 4-acylpyrazole derivatives are directly prepared from saturated ketones and hydrazones featured with multiple aliphatic C–H bond functionalization and C–C bond cleavage and reorganization. Compared with literature methods, this novel process has advantages such as simple and economical starting materials, a sustainable oxidant, excellent regioselectivity, and good efficiency

Rhodium(III)-Catalyzed Redox-Neutral Synthesis of Isoquinolinium Salts via C–H Activation of Imines

Redox-neutral synthesis of isoquinolinium salts via C–H activation of presynthesized or in situ formed imines and coupling with α-diazo ketoesters has been realized, where a zinc salt promotes cyclization as well as provides a counteranion. Under three-component conditions, both ketone and aldehydes are viable arene sources. The coupling of imines with diazo malonates under similar conditions afforded isoquinolin-3-ones as the coupling product

Decomposition Algorithm for the Scheduling of Typical Polyvinyl Chloride Production by Calcium Carbide Method

In our previous work (Tian et al. <i>Ind. Eng. Chem. Res.</i> <b>2016</b>, 55(21), 6161–6174), a plantwide scheduling model was presented, which was difficult to solve for industrial scale instances in acceptable time. Because the vinyl chloride monomer (VCM) buffer links the continuous process with the batch process, the whole scheduling problem can be decomposed into the upstream VCM production processes and the downstream polymerization processes. Thus, a decomposition algorithm is presented in this paper to accelerate the computation progress. Using the decomposition algorithm, the polymerization scheduling optimization problem is first conducted and thus the detailed VCM demand schedule is obtained. Then, with an off-line model formulated in advance, the operating states (i.e., start/stop operations) of arc furnaces are optimized in the second step, which would be the hard-to-solve binary variables in the plantwide scheduling model. In the off-line work, the furnaces operating range (i.e., the production rate) is discretized into multiple operational levels and the corresponding optimal furnaces selection scheme is then obtained based on the energy consumption model of the arc furnaces. Finally, the determined binary variables are embedded into the plantwide scheduling model and thus a reduced scale scheduling optimization is executed. Computational results show that the proposed algorithm can accelerate the computation greatly and the scheduling results are close to or even better than those given in our previous work

Synthesis of α‑Formylated <i>N</i>‑Heterocycles and Their 1,1-Diacetates from Inactivated Cyclic Amines Involving an Oxidative Ring Contraction

A novel synthesis of pyrrolidine-2-carbaldehydes or tetrahydropyridine-2-carbaldehydes from the cascade reactions of <i>N</i>-arylpiperidines or <i>N</i>-arylazepanes is presented. Mechanistically, the formation of the title compounds involves an unprecedented oxidative ring contraction of inactivated cyclic amines via Cu­(OAc)₂/KI/O₂-promoted oxidative cleavage and reformation of the C–N bond. Interestingly, when PhI­(OAc)₂ was used in place of KI, 1,1-diacetates of the corresponding aldehydes were directly obtained with good efficiency. To the best of our knowledge, this is the first example of regioselective C­(sp³)–H bond functionalization and C­(sp³)–N bond activation of saturated cyclic amines using copper salt and oxygen