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This study reports an efficient and green one‐step method for synthesizing thiophene‐substituted ketones from 2‐thiophenemethanol and ketones via dehydrogenative coupling using manganese complexes as catalysts. The manganese complex demonstrated a broad applicability under mild conditions and extended the range of usable substrates. Utilizing this strategy, we carried out an efficient and diverse reaction of ketones with 2‐thiophenemethanol, and successfully synthesized a series of thiophene‐substituted saturated ketones and α, β‐unsaturated ketones in good isolated yields. [ABSTRACT FROM AUTHOR]

Herein, an efficient and green procedure for the synthesis of tetrahydro‐β‐carbolines via dehydrogenative coupling of alcohols with tryptamines is reported. The reaction was carried out under mild conditions in the presence of a catalytic amount of the iPrPNP−Mn catalyst and a weak base (Na2CO3). This method tolerated a variety of benzylic and aliphatic alcohol substrates with different functional groups and afforded diverse products in good to excellent isolated yields using tryptamines. Using this strategy, we successfully synthesised pharmaceutical molecules harman, harmaline, and harmine in a concise manner. [ABSTRACT FROM AUTHOR]

Herein we report a Pd‐catalyzed asymmetric allenylic alkylation strategy for the direct functionalization of 1H‐indoles by employing P‐chiral BIBOP‐type ligands. The regioselectivity (N1/C3) of this process can be switched efficiently. Using Cs2CO3 at elevated temperatures in MeCN, N1‐alkylated indoles bearing axial chirality with a stereocenter non‐adjacent (β) to the nitrogen are produced in good yields with high enantioselectivity and complete N1‐regioselectivity regardless of the electronic properties and substitution patterns of diverse indoles. Using K2CO3 at room temperature in CH2Cl2, chiral C3‐alkylated indoles can also be obtained. Notably, we introduce a new class of tri‐substituted allenylic electrophiles that proceeded through different pathways from di‐substituted allenylic electrophiles. [ABSTRACT FROM AUTHOR]

Quasi‐two‐dimensional perovskite solar cells (quasi‐2D PSCs) have drawn significant attention and are rapidly developing owing to the impressive stability of the materials and devices. However, there are no reliable guidelines for designing and selecting suitable organic spacer cations to achieve high power conversion efficiency (PCE) in quasi‐2D PSCs. Herein, the effects of the spacer cations with different substituents, i.e., benzylamine (PMA), 4‐methoxybenzylamine (p‐MeOPMA), and 4‐fluorobenzylamine (p‐FPMA), on the optoelectronic properties and device performance of quasi‐2D perovskites are systematically investigated. It is found that the spacer cations with different substituents mainly affect the crystal growth and film quality of quasi‐2D perovskites. Interestingly, quasi‐2D perovskites based on p‐MeOPMA or p‐FPMA exhibit poor crystallinity and crystal orientation, while quasi‐2D perovskite based on the unsubstituted PMA shows improved crystallinity and crystal orientation, which enables suppressed trap densities and efficient charge transport. The PMA‐based quasi‐2D perovskite (nominal n = 3) solar cell exhibits the highest PCE of 13.58%. These results demonstrate that the rational regulation of organic spacer cations plays a crucial role in improving the crystallinity and crystal orientation of perovskite films and elucidate key guiding rules for organic spacer cations for high‐performance quasi‐2D PSCs. [ABSTRACT FROM AUTHOR]

A method for the asymmetric construction of functionalized acyclic all‐carbon quaternary stereocenters and 1,3‐nonadjacent stereoelements has been developed via organo/metal dual catalyzed asymmetric allenylic substitution of branched and linear aldehydes, by developing an unknown acyclic secondary‐secondary diamine as the enabling organocatalyst. Although it is believed that secondary‐secondary diamines are difficult to be used as the organocatalysts in organo/metal dual catalysis, this study demonstrates that such diamines can be successfully combined with a metal catalyst in organo/metal dual catalysis. Our study enables the asymmetric construction of two important classes of motifs which were previously difficult to access, axially chiral allene‐containing acyclic all‐carbon quaternary stereocenters and 1,3‐nonadjacent stereoelements bearing allenyl axial chirality and central chirality, in good yields with high enantio‐ and diastereoselectivity. [ABSTRACT FROM AUTHOR]

In this paper, CexSn1−xOy–F (x = 1, 0.75, 0.5, 0.25, 0) and CexSn1−xOy–A were prepared through a typical reverse co-precipitation method. The experimental results showed that Sn doping could improve the activity and thermal stability of CeO2 in different modes. Comparing the activity and characterization of CexSn1−xOy–F and CexSn1−xOy–A, the improvement of catalyst activity was attributed to the Ce–O–Sn structure with more oxygen vacancies formed by Sn doping, whereas the enhancement of thermal stability was related to the Sn2+ remaining in the CeO2 lattice after accelerated aging. Therefore, a mechanism was proposed that Ce4+–O–Sn2+ is more stable than Ce4+–O–Sn4+ in CexSn1−xOy solid solution. [ABSTRACT FROM AUTHOR]

The catalytic dehydrogenation of alcohols is essential for the sustainable production of valuable products. This provides a new strategy for green organic synthesis in chemical industries. Herein, we describe a manganese‐based catalytic system that enables the efficient synthesis of C3‐alkylated indoles from benzyl alcohols and indoles via the borrowing hydrogen process. Furthermore, dehydrogenative coupling of 2‐arylethanols and indoles yields C3‐alkenylated indoles. Meanwhile, reacting 2‐aminophenethanol instead of indoles can also obtain the corresponding indole products with high selectivity under the same conditions. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The development of an efficient and sustainable synthetic route for formaldehyde production from renewable feedstock, especially in combination with a subsequent transformation to straightforwardly construct valuable chemicals, is highly desirable. Herein, we report a novel manganese‐catalyzed dehydrogenative cyclization of methanol as a formaldehyde surrogate with a variety of dinucleophiles for facile synthesis of N‐heterocycles. The in situ generated formaldehyde via catalytic methanol dehydrogenation can be selectively trapped by diverse dinucleophiles to avoid several possible side reactions. The utility of this transformation is further highlighted by its successful application to the synthesis of 13C‐labeled N‐heterocycles using 13CH3OH as a readily accessible 13C‐isotope reagent. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: A Pd‐catalyzed asymmetric aromative [4+3]‐cyclization reaction of amino‐trimethylenemethanes (TMM, 1,3‐dipoles) with fused 1‐azadienes has been developed. This method enables access to the synthetically importance and biologically active benzofuran fused azepines and indeno‐azepines in excellent efficiency and stereoselectivity (up to 95% yield, 99% ee, >19 : 1 dr). [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: Catalytic hydrogenation of esters is essential for the sustainable production of alcohols in organic synthesis and chemical industry. Herein, we describe the first non‐noble metal catalytic system that enables an efficient hydrogenation of non‐activated esters to alcohols in the absence of phosphine ligands (with a maximum turnover number of 2391). The general applicability of this protocol was demonstrated by the high‐yielding hydrogenation of 39 ester substrates including aromatic/aliphatic esters, lactones, polyesters and various pharmaceutical molecules. [ABSTRACT FROM AUTHOR]

The strong binding ability of P‐ylides with transition metals limits the utilization of stabilized P‐ylide as nucleophiles in asymmetric organometallic catalysis. Herein we describe the first rhodium‐catalyzed asymmetric ring‐opening reaction of P‐ylides utilizing oxabicyclic alkenes as the electrophilic partner. Various P‐ylides including ester‐, ketone‐ and amide‐style P‐ylides are all applicable. This asymmetric reaction occurs through the cleavage of two bridgehead C−O bonds and the formation of two C−C bonds, and oxabenzonorbornadienes are used as 1,4‐biselectrophiles, thus providing access to benzonorcaradienes in good yields with high enantioselectivity and perfect diastereoselectivity. The present protocol also constitutes the first highly enantioselective direct catalytic asymmetric cyclopropanation of stabilized P‐ylide nucleophiles. [ABSTRACT FROM AUTHOR]

Isobutanol serves as an ideal gasoline additive owing to its good compatibility with current engine technology, high energy density, and high octane number. Herein, an efficient and selective Mn‐catalyzed upgrading of ethanol with methanol into isobutanol is reported. This is the first example of deoxygenative coupling of lower alcohols to isobutanol by using a homogeneous non‐noble‐metal catalyst. This transformation proceeded at very low catalyst loading with a high turnover number (9233) and up to 96 % isobutanol selectivity. [ABSTRACT FROM AUTHOR]

The first Pd‐catalyzed asymmetric allenylic [4+1] cycloaddition was successfully developed. Alternatively, tuning the Pd catalyst switched the reactivity toward an unprecedented [4+3] cycloaddition/cross‐coupling. Ligands play a vital role in controlling the reaction pathway, allowing highly selective access to different products from identical substrates. Biological evaluation of the obtained compounds led to the discovery of new antitumor targets. A possible mechanism is proposed, suggesting two interesting catalytic cycles for the cycloaddition with palladium‐butadienyls. This study also demonstrated the potential and utility of allenic esters as 1,4‐biselectrophiles and C4 synthons for participating in cycloaddition reactions. Switch it: The use of metal‐butadienyl species in a cycloaddition is exemplified by the first Pd‐catalyzed asymmetric allenylic [4+1] cycloaddition. Notably, tuning the Pd catalysts switched the reactivity toward an unprecedented [4+3] cycloaddition/cross‐coupling. These reactions lead to diverse and valuable carbocycles and heterocycles, and also provide a straightforward synthesis to [3]dendralenes. [ABSTRACT FROM AUTHOR]

Reported herein is a general and efficient dual‐deoxygenative coupling of primary alcohols with 2‐arylethanols catalyzed by a well‐defined Mn/PNP pincer complex. This reaction is the first example of the catalytic dual‐deoxygenation of alcohols using a non‐noble‐metal catalyst. Both deoxygenative homocoupling of 2‐arylethanols (17 examples) and their deoxygenative cross‐coupling with other primary alcohols (20 examples) proceeded smoothly to form the corresponding alkenes by a dehydrogenation and deformylation reaction sequence. "Mn" of action: A general and efficient dual‐deoxygenative coupling of primary alcohols with 2‐arylethanols, catalyzed by a well‐defined manganese/PNP pincer complex, is reported. Mechanistic studies indicate that this transformation undergoes a reaction process involving catalytic dehydrogenation, aldol condensation, and base‐promoted deformylation. [ABSTRACT FROM AUTHOR]

The application potential of primary amine catalysts in the context of Mannich reactions of aldehydes with ketimines is exemplified by isatin-derived ketimines and cyclic trifluoromethyl ketimines. Primary amine catalysts exhibit either unusual stereoselectivity or reactivity, which is not observable with secondary amine catalysts. Moreover, reversal of diastereofacial selectivity between primary and secondary amine catalysts is disclosed. These new reactions provide useful methods for the syntheses of chiral 3-substituted 3-amino-2-oxindoles and dihydroquinazolinones bearing a trifluoromethylated quaternary stereocenter. The synthetic utility of the reactions is demonstrated through the formal synthesis of AG-041R and DPC 083 and the total synthesis of (−)-psychotriasine. [ABSTRACT FROM AUTHOR]