2819-12-7

Upstream product

• 26029-34-5 2-methyl-3-phenyl-2-cyclopentenone 
• 1120-73-6 2-methyl-2-cyclopenten-1-one 
• 108-98-5 thiophenol 
• 25112-86-1 2-Methylcyclopent-1,3-dione monoethyl enol ether 
• 100-58-3 phenylmagnesium bromide 
• 98-80-6 phenylboronic acid 
• 4407-36-7 (2E)-3-phenyl-2-propen-1-ol 
• 80586-92-1 [(E)-3-(prop-2-enyloxy)-propenyl]benzene 
• 42436-86-2 2-phenylcyclobutanone 
• 106987-90-0 1-chloro-2-(ethylsulfinyl)benzene 
• 1821-12-1 4-Phenylbutyric acid 
• 18496-54-3 phenylbutyric acid chloride 
• 83187-70-6 2-Diazo-6-phenylhexan-3-one 
• 186581-53-3 diazomethane 

Downstream Products

• 57374-45-5 1-Acetoxy-2-methyl-3-phenyl-cyclopenten 
• 26029-34-5 2-methyl-3-phenyl-2-cyclopentenone 

Relevant academic research and scientific papers

Asymmetric Michael addition reactions using a chiral La-Na aminodiolate catalyst

(R,R)-(+)-2-[Benzyl-(2-hydroxy-2-phenylethyl)amino]-1-phenylethanol 1 is used as a chiral ligand in the synthesis of an optically active lanthanum-sodium amino diol complex LS-1. This heterobimetallic catalyst is quite effective as an asymmetric catalyst for various Michael addition reactions, 1H NMR study indicates the co-ordination of enone to the central lanthanum atom in LS-1. The reaction conditions were optimized and the adducts were obtained in high yield with moderate to high enantiomeric excess under extremely mild conditions.

Mechanistic Insights into the Formation of δ-Lactones by Cerium-Catalyzed Aerobic Coupling of β-Oxoesters with Enol Acetates

δ-Valerolactone derivatives are formed by the cerium-catalyzed, aerobic coupling of β-oxoesters with enol acetates and dioxygen. The products possess a 1,4-diketone moiety, thus, the conversion can be regarded as an Umpolung since the β-oxoesters are oxidized to electrophilic α-radicals. The transformation has similarities to the Baeyer-Villiger oxidation (BVO) where the higher substituted residue migrates. An endoperoxidic oxycarbenium ion comparable to the Criegee intermediate in the BVO is proposed as a reaction intermediate in this case of the oxidative C?C coupling reaction, but in contrast to the BVO, the less substituted alkyl residue migrates. It was demonstrated by the conversion of β-oxoesters with two stereocenters that this 1,2-alkyl shift proceeds with retention of configuration. A radical chain mechanism of the coupling reaction was furthermore evidenced by the conversion of enol acetates and β-oxoesters with cyclopropyl substituents. Isolation and characterization of products with opened cyclopropane rings established the constitution of radical intermediates.

Diastereoselective Palladium-Catalyzed Conjugate Addition of Arylboronic Acids to α-Substituted Cyclic Enones

A palladium-catalyzed conjugate addition of arylboronic acids to α-substituted cyclic enones was developed to give α,β-disubstituted ketones with high diastereoselectivity. Mechanistic investigation showed that the high diastereoselectivity was realized through epimerization.

Rhodium-catalyzed olefin isomerization/allyl claisen rearrangement/ intramolecular hydroacylation cascade

It has been established that a cationic Rh(I)/dppf complex catalyzes the olefin isomerization/allyl Claisen rearrangement/intramolecular hydroacylation cascade of di(allyl) ethers to produce substituted cyclopentanones in good yields under mild conditions.

α-Diazo-β-ketonitriles: Uniquely reactive substrates for arene and alkene cyclopropanation

An investigation of the intramolecular cyclopropanation reactions of α-diazo-β-ketonitriles is reported. These studies reveal that α-diazo-β-ketonitriles exhibit unique reactivity in their ability to undergo arene cyclopropanation reactions; other similar acceptor-acceptor- substituted diazo substrates instead produce mixtures of C-H insertion and dimerization products. α-Diazo-β-ketonitriles also undergo highly efficient intramolecular cyclopropanation of tri- and tetrasubstituted alkenes. In addition, the α-cyano-α-ketocyclopropane products are demonstrated to serve as substrates for SN2, SN2′, and aldehyde cycloaddition reactions.

Conjugate reduction of α,β-unsaturated carbonyl compounds catalyzed by a copper carbene complex

(Matrix presented) An N-heterocyclic carbene copper chloride (NHC-CuCl) complex (2) has been prepared and used to catalyze the conjugate reduction of α,β-unsaturated carbonyl compounds. The combination of catalytic amounts of 2 and NaOt-Bu with poly(methy

Palladium-Catalyzed Intermolecular Arylation of Functionally-Substituted Cycloalkenes by Aryl Iodides

The palladium-catalyzed, intermolecular arylation of functionally-substituted cycloalkenes by aryl iodides affords a new synthetic route to a variety of arylated cyclic derivatives.The arylation of 2-cyclopenten-1-ol and 2-cyclo-hexen-1-ol provides modest yields of the corresponding 3-arylcycloalkanones, while 2-methyl-2-cyclopenten-1-ol affords a mixture of singly and doubly arylated cyclopentanone produts. 1-Acetoxycyclopentene undergoes arylation to produce the corresponding allylic aryl substitution product opening up a new route for the α-arylation of cycloalkanones.Cyclic allylic ethers undergo arylation at both ends of the C-C double bond to generate mixtures of singly arylated vinylic ethers. 1-Cyanocylopentene reacts with aryl iodides under palladium catalysis to produce 1-cyano-5-arylcyclopentenes in high yield. 2-Methyl-2-cycloalken-1-ones afford modest yields of doubly arylated 2-cycloalken-1-ones in a single step.

The Intramolecular Buchner Reaction of Aryl Diazoketones. Substituent Effects and Scope in Synthesis

Rhodium(II) acetate-catalysed cyclisation of α-diazoketones derived from 3-arylpropionic acid produces bicyclodecatrienones or 2-tetralones depending on the substitution pattern of the aryl ring in the precursor; the former products are transformed into the latter catalytically with trifluoroacetic acid.Precursors with methyl, methoxy, and acetoxy substituents have been examined, efficient cyclisation occurring in all cases.When the precursor contains a meta-methoxy substituent, 2-tetralones are obtained directly.The efficient conversion of 3-phenylpropionicacid into trans-1-methylbicyclodecan-2-one is also described, partial asymmetric synthesis having been realised through the use of rhodium (S)-mandelate as the cyclisation catalyst.Cyclisations of diazoketones derived from 4-phenylbutyric acid and 5-phenylpentanoic acid have also been studied; the former provides a new entry into the bicycloundecane system whereas the latter produces a 2,3-disubstituted cyclopentanone via C-H insertion.Aspects of the cycloheptatriene-norcaradiene equilibrium in fused ring systems are discussed.

Ring Expansion of Cyclobutanones to Cyclopentanones via α-Lithioalkyl Aryl Sulfoxides and Selenoxides

Reaction of α-lithioalkyl 2-chlorophenyl sulfoxides (prepared from the corresponding sulfoxides and LDA) with cyclobutanones affords adducts which undergo ring expansion to cyclopentanones upon treatment with potassium hydride.This reaction only works for cyclobutanones substituted at C2 with at least one phenyl or alkenyl group (type I and type II cyclobutanones).Cyclobutanones substituted at C2 with at least one alkyl group (type III and type IV cyclobutanones) undergo similar ring expansion upon treatment with α-lithioalkylphenyl selenoxides followed by direct thermolysis of the adducts.With both the sulfoxide and selenoxide reagents, the carbon atom inserted into the cyclobutanone can be unsubstituted, monosubstituted, or disubstituted.The ring expansions of 17 different cyclobutanones to 29 different cyclopentanones are presented.