BIMP Catalyzed 1,3-Prototropic Shift for the Highly Enantioselective Synthesis of Conjugated Cyclohexenones

<div>A bifunctional iminophosphorane (BIMP) catalyzed enantioselective synthesis of α,β-unsaturated cyclohexenones via a facially selective 1,3-prototropic shift of β,γ-unsaturated prochiral isomers, under mild reaction conditions and in short reaction times, on a range of structurally diverse substrates, is reported. α,β-Unsaturated cyclohexenone products primed for downstream derivatisation were obtained in high yields (up to 99%) and consistently high enantioselectivity (up to 99% ee). In-depth studies into the reaction mechanism and origins of enantioselectivity, including multivariate linear regression of TS energy, were carried out computationally on the catalytic system and the obtained data was found to be in good agreement with experimental findings.</div>

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Cs2CO3/[bmim]Br as an Efficient, Green, and Reusable Catalytic System for the Synthesis of N-Alkyl Derivatives of Phthalimide under Mild Conditions

Research Letters in Organic Chemistry ◽

10.1155/2008/419054 ◽

2008 ◽

Vol 2008 ◽

pp. 1-4 ◽

Cited By ~ 2

Author(s):

Alireza Hasaninejad ◽

Abdolkarim Zare ◽

Ahmad Reza Moosavi-Zare ◽

Fatemeh Khedri ◽

Rahimeh Rahimi ◽

...

Keyword(s):

Ionic Liquid ◽

Catalytic System ◽

Reaction Times ◽

Catalytic Amount ◽

Conjugate Addition ◽

Reaction Conditions ◽

Mild Conditions ◽

Alkyl Derivatives ◽

High Yields ◽

Derivatives Of

Aza-conjugate addition of phthalimide to α,β-unsaturated esters efficiently achieves in the presence of catalytic amount of Cs2CO3 and ionic liquid 1-butyl-3-methylimidazolium bromide ([bmim]Br) under mild reaction conditions (70°C) to afford N-alkyl phthalimides in high yields and relatively short reaction times.

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Ring-Opening Copolymerization of Cyclohexene Oxide and Cyclic Anhydrides Catalyzed by Bimetallic Scorpionate Zinc Catalysts

Polymers ◽

10.3390/polym13101651 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1651

Author(s):

Felipe de la Cruz-Martínez ◽

Marc Martínez de Sarasa Buchaca ◽

Almudena del Campo-Balguerías ◽

Juan Fernández-Baeza ◽

Luis F. Sánchez-Barba ◽

...

Keyword(s):

Catalytic Activity ◽

Reaction Mechanism ◽

Catalytic System ◽

Phthalic Anhydride ◽

Ring Opening ◽

High Selectivity ◽

Zinc Complexes ◽

Cyclohexene Oxide ◽

Reaction Conditions ◽

Cyclic Anhydrides

The catalytic activity and high selectivity reported by bimetallic heteroscorpionate acetate zinc complexes in ring-opening copolymerization (ROCOP) reactions involving CO2 as substrate encouraged us to expand their use as catalysts for ROCOP of cyclohexene oxide (CHO) and cyclic anhydrides. Among the catalysts tested for the ROCOP of CHO and phthalic anhydride at different reaction conditions, the most active catalytic system was the combination of complex 3 with bis(triphenylphosphine)iminium as cocatalyst in toluene at 80 °C. Once the optimal catalytic system was determined, the scope in terms of other cyclic anhydrides was broadened. The catalytic system was capable of copolymerizing selectively and efficiently CHO with phthalic, maleic, succinic and naphthalic anhydrides to afford the corresponding polyester materials. The polyesters obtained were characterized by spectroscopic, spectrometric, and calorimetric techniques. Finally, the reaction mechanism of the catalytic system was proposed based on stoichiometric reactions.

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Correlation between FA and ADC, number and length of the periprostatic neurovascular fibers

Urologia Journal ◽

10.1177/03915603211063769 ◽

2021 ◽

pp. 039156032110637

Author(s):

Valerio Di Paola ◽

Angelo Totaro ◽

Giacomo Avesani ◽

Benedetta Gui ◽

Andrea Boni ◽

...

Keyword(s):

Regression Analysis ◽

Linear Regression ◽

Negative Correlation ◽

Multivariate Regression ◽

Linear Regression Analysis ◽

Multivariate Linear Regression ◽

Multivariate Linear Regression Analysis ◽

Independent Variables ◽

Fiber Tracts ◽

Good Agreement

Purpose: Our aim was to explore the relation between FA and ADC, number and length of the periprostatic neurovascular fibers (PNF) by means of 1.5 T Diffusion Tensor Imaging (DTI) imaging through a multivariate linear regression analysis model. Methods: For this retrospective study, 56 patients (mean age 63.5 years), who underwent 1.5-T prostate MRI, including DTI, were enrolled between October 2014 and December 2018. Multivariate regression analysis was performed to evaluate the statistically significant correlation between FA values (dependent variable) and ADC, the number and the length of PNF (independent variables), if p-value <0.05. A value of 0.5 indicated poor agreement; 0.5–0.75, moderate agreement; 0.75–0.9, good agreement; 0.61–0.80, good agreement; and 0.9–1.00, excellent agreement. Results: The overall fit of the multivariate regression model was excellent, with R2 value of 0.9445 ( R2 adjusted 0.9412; p < 0.0001). Multivariate linear regression analysis showed a statistically significant correlation ( p < 0.05) for all the three independent variables. The r partial value was −0.9612 for ADC values ( p < 0.0001), suggesting a strong negative correlation, 0.4317 for the number of fiber tracts ( p < 0.001), suggesting a moderate positive correlation, and −0.306 for the length of the fiber tracts ( p < 0.05), suggesting a weak negative correlation. Conclusions: Our multivariate linear regression model has demonstrated a statistically significant correlation between FA values of PNF with other DTI parameters, in particular with ADC.

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Ultrasound-promoted organocatalytic enamine–azide [3 + 2] cycloaddition reactions for the synthesis of ((arylselanyl)phenyl-1H-1,2,3-triazol-4-yl)ketones

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.13.68 ◽

2017 ◽

Vol 13 ◽

pp. 694-702 ◽

Cited By ~ 6

Author(s):

Gabriel P Costa ◽

Natália Seus ◽

Juliano A Roehrs ◽

Raquel G Jacob ◽

Ricardo F Schumacher ◽

...

Keyword(s):

Reaction Times ◽

Cycloaddition Reactions ◽

Reaction Conditions ◽

Keto Esters ◽

Efficient Access ◽

High Yields ◽

Short Times

The use of sonochemistry is described in the organocatalytic enamine–azide [3 + 2] cycloaddition between 1,3-diketones and aryl azidophenyl selenides. These sonochemically promoted reactions were found to be amenable to a range of 1,3-diketones or aryl azidophenyl selenides, providing an efficient access to new ((arylselanyl)phenyl-1H-1,2,3-triazol-4-yl)ketones in good to excellent yields and short reaction times. In addition, this protocol was extended to β-keto esters, β-keto amides and α-cyano ketones. Selanyltriazoyl carboxylates, carboxamides and carbonitriles were synthesized in high yields at short times of reaction under very mild reaction conditions.

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Deoxyfluorination of acyl fluorides to trifluoromethyl compounds by FLUOLEAD®/Olah’s reagent under solvent-free conditions

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.16.254 ◽

2020 ◽

Vol 16 ◽

pp. 3052-3058

Author(s):

Yumeng Liang ◽

Akihito Taya ◽

Zhengyu Zhao ◽

Norimichi Saito ◽

Norio Shibata

Keyword(s):

Reaction Mechanism ◽

Solvent Free ◽

Reaction Conditions ◽

Great Tolerance ◽

Solvent Free Conditions ◽

Synthetic Drug ◽

High Yields

A new protocol enabling the formation of trifluoromethyl compounds from acyl fluorides has been developed. The combination of FLUOLEAD® and Olah’s reagent in solvent-free conditions at 70 °C initiated the significant deoxyfluorination of the acyl fluorides and resulted in the corresponding trifluoromethyl products with high yields (up to 99%). This strategy showed a great tolerance for various acyl fluorides containing aryloyl, (heteroaryl)oyl, or aliphatic acyl moieties, providing good to excellent yields of the trifluoromethyl products. Synthetic drug-like molecules were also transformed into the corresponding trifluoromethyl compounds under the same reaction conditions. A reaction mechanism is proposed.

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Infrared Irradiation-Assisted Multicomponent Synthesis of 2-Amino-3-cyano-4H-pyran Derivatives

Journal of the Mexican Chemical Society ◽

10.29356/jmcs.v56i2.308 ◽

2017 ◽

Vol 56 (2) ◽

Author(s):

Arturo Sánchez ◽

Fernando Hernández ◽

Paulo César Cruz ◽

Yolanda Alcaraz ◽

Joaquín Tamariz ◽

...

Keyword(s):

Ethyl Acetoacetate ◽

Present Method ◽

Reaction Times ◽

Ammonium Hydroxide ◽

Infrared Irradiation ◽

Efficient Synthesis ◽

Multicomponent Synthesis ◽

Reaction Conditions ◽

High Yields ◽

Pyran Derivative

A simple, versatile, and efficient synthesis of 4<em>H</em>-pyran derivative compounds is achieved via a three-component cyclocondensation of aldehydes, malononitrile, and ethyl acetoacetate, using ammonium hydroxide as the catalyst, promoted by infrared irradiation. The present method offers several advantages, such as high yields, non hazardous reaction conditions as well as short reaction times.

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One-pot, three-component synthesis of pyrrolo[2,3-d]pyrimidine derivatives

Journal of the Mexican Chemical Society ◽

10.29356/jmcs.v62i1.340 ◽

2018 ◽

Vol 62 (1) ◽

Author(s):

Jabbar Khalafy ◽

Ramin Javahershenas

Keyword(s):

Simple Procedure ◽

Reaction Times ◽

Pyrimidine Derivatives ◽

Reaction Conditions ◽

One Pot ◽

General Applicability ◽

Green Approach ◽

Three Component Reaction ◽

High Yields ◽

Work Up

<p>A green approach for the synthesis of polyfunctionalized pyrrolo[2,3-<em>d</em>]pyrimidine derivatives was successfully achieved by a one-pot, three-component reaction of arylglyoxals, 6-amino-1,3-dimethyluracil and barbituric acid derivatives in the presence of tetra-<em>n</em>-butylammonium bromide (TBAB) (5 mol%) as the catalyst in ethanol at 50 °C. This protocol has many advantages such as high yields (73-95%), green and simple procedure, short reaction times, easy work-up, mild reaction conditions and general applicability.</p>

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A Simple and Green Procedure for the Synthesis of 5-Arylidenerhodanines Catalyzed by Diammonium Hydrogen Phosphate in Water

The Scientific World JOURNAL ◽

10.1155/2013/543768 ◽

2013 ◽

Vol 2013 ◽

pp. 1-4

Author(s):

Liangliang Han ◽

Tao Wu ◽

Zhongqiang Zhou

Keyword(s):

Reaction Times ◽

Aromatic Aldehydes ◽

Hydrogen Phosphate ◽

Reaction Conditions ◽

Efficient Procedure ◽

Diammonium Hydrogen Phosphate ◽

High Yields ◽

Green Procedure ◽

Work Up ◽

Diammonium Hydrogen

A simple and efficient procedure for the synthesis of 5-arylidenerhodanines by condensation of aromatic aldehydes with rhodanine in water using diammonium hydrogen phosphate as catalyst is described. The procedure offers several advantages including environmentally friendly, mild reaction conditions, short reaction times, high yields, and simple experimental and work-up procedures.

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Regio- and Diastereoselective Synthesis of Novel Polycyclic Pyrrolo[2,1-a]isoquinolines Bearing Indeno[1,2-b]quinoxaline Moieties by a Three-Component [3+2]-Cycloaddition Reaction

Synlett ◽

10.1055/s-0039-1690768 ◽

2019 ◽

Vol 31 (03) ◽

pp. 267-271 ◽

Cited By ~ 2

Author(s):

Firouz Matloubi Moghaddam ◽

Atiyeh Moafi ◽

Behzad Jafari ◽

Alexander Vilinger ◽

Peter Langer

Keyword(s):

Cycloaddition Reaction ◽

Reaction Times ◽

Dipolar Cycloaddition ◽

Diastereoselective Synthesis ◽

X Ray Diffraction ◽

Reaction Conditions ◽

One Pot ◽

Three Component Reaction ◽

Relative Stereochemistry ◽

High Yields

A regio- and diastereoselective synthesis of 2,3-dihydro-10b′H-spiro[indeno[1,2-b]quinoxaline-11,1′-pyrrolo[2,1-a]isoquinoline]-2′,3′-diylbis(phenylmethanone) derivatives containing four contiguous chiral stereocenters was achieved through 1,3-dipolar cycloaddition of isoquinolinium N-ylides in a one-pot three-component reaction. The desired products were obtained in short reaction times and in moderate to high yields (up to 92%) under relatively mild reaction conditions. The structure and relative stereochemistry of the desired product was confirmed by X-ray diffraction analysis.

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