4581-74-2

Basic information

• Product Name: [4S,(-)]-4,4aα,5,6-Tetrahydro-4β,7-dimethylcyclopenta[c]pyran-1(3H)-one
• Synonyms: (-)-Neonepetalactone;[4S,(-)]-4,4aα,5,6-Tetrahydro-4β,7-dimethylcyclopenta[c]pyran-1(3H)-one;Neonepetalactone
• CAS NO: 4581-74-2
• Molecular Formula: C10H14O2
• Molecular Weight: 166.21696
• Mol File: 4581-74-2.mol
• Article Data: 4

Chemical Properties

• Appearance: /
• CAS DataBase Reference: [4S,(-)]-4,4aα,5,6-Tetrahydro-4β,7-dimethylcyclopenta[c]pyran-1(3H)-one(CAS DataBase Reference)
• NIST Chemistry Reference: [4S,(-)]-4,4aα,5,6-Tetrahydro-4β,7-dimethylcyclopenta[c]pyran-1(3H)-one(4581-74-2)
• EPA Substance Registry System: [4S,(-)]-4,4aα,5,6-Tetrahydro-4β,7-dimethylcyclopenta[c]pyran-1(3H)-one(4581-74-2)

Safety Data

• Hazardous Substances Data: 4581-74-2(Hazardous Substances Data)

Upstream product

• 21700-60-7 metatabiether 
• 77614-35-8 (3R,8S)-1-methyl-2-formyl-3(β-acetoxy-isopropyl)cyclopentene 
• 937035-21-7 (4S,8R/S)-p-menth-1-en-9-ol 
• 28839-13-6 (4S,8R/S)-p-menth-1-en-9-yl acetate 
• 66884-89-7 (R,S)-Dehydroiridodial 
• 5989-54-8 (-)-(S)-limonene 
• 205496-91-9 (R)-2-(2,2-Dimethyl-propionyloxy)-5-{(S)-2-[(E)-(S)-2-methoxymethyl-pyrrolidin-1-ylimino]-1-methyl-ethyl}-cyclopent-1-enecarboxylic acid methyl ester 
• 205496-89-5 (1R,2R,1'S,2''S)-2-[2-(2''-methoxymethylpyrrolidin-1-ylimino)-1'-methylethyl]-5-oxo-cyclopentanecarboxylic acid methylester 
• 188493-18-7 (R)-2-Methyl-5-((S)-1-methyl-2-oxo-ethyl)-cyclopent-1-enecarboxylic acid methyl ester 
• 76792-78-4 (R,S)-Dehydroiridodiol 
• 131690-94-3 (S)-2-(Diethoxy-phosphoryloxy)-5-((R)-1-methyl-allyl)-cyclopent-1-enecarboxylic acid ethyl ester 
• 131690-88-5 (R)-2-((S)-1-Methyl-allyl)-5-oxo-cyclopentanecarboxylic acid ethyl ester 
• 131690-96-5 (R)-2-Methyl-5-((S)-1-methyl-allyl)-cyclopent-1-enecarboxylic acid ethyl ester 
• 57020-97-0 ethyl 5-oxocyclopent-1-en-1-carboxylate 

Downstream Products

• 76792-78-4 (R,S)-Dehydroiridodiol 

Relevant articles and documents

A short asymmetric synthesis of (-)-neonepetalactone

(4S.,4aR)-Neonepetalactone (6) was synthesized in high diastereomeric and enantiomeric purity (de, ee ≥ 96 %) in a four step procedure. Key step of the total synthesis is the Michael addition of metalated propanal SAMP-hydrazone ((S)-1) to 2-cyclopentenecarboxylate (2).

Reaction of Organoaluminium Reagents with Cyclopropylmethyl Acetates and 2-Vinylcyclopropane-1,1-dicarboxylate Esters

Ring-opening alkylation of cyclopropylmethyl acetates was studied.The acetoxyl group of 7-(1-acetoxyheptyl)norcarane is substituted by the alkyl group upon treatment with trialkylaluminium, but alkylation of trans-1-(1-acetoxyethyl)-2-phenylcyclopropane with trialkylaluminium gives rise to trans-5-phenyl-2-alkenes.The reaction of (1S,2S)-2-phenylcyclopropylmethyl acetate with trimethylaluminium resulted in the complete loss of optical activity to give racemic 4-phenyl-1-pentene.Alkylation of trans-1-(1-acetoxy-3-phenylpropyl)-2-vinylcyclopropane with trialkylaluminium proceeds under regioselective ring-opening to give 3-alkylated trans-8-phenyl-1,5-octadiene (selectivity 73-83percent).The regio- and stereochemistry of homoconjugate addition to activated vinylcyclopropanes having a doubly carbonyl substituted ring carbon was studied.Trialkylaluminium on addition to diethyl 2-vinylcyclopropane-1,1-dicarboxylate in a 1,5-manner afford diethyl (2-alkyl-3-butenyl)propanedioate (over 96percent selectivity).In contrast, the reaction of this cyclopropane with tetraalkylaluminiumlithium takes place in a 1.7-manner to give diethyl (trans-4-alkyl-2-butenyl)propanedioate with 88-92percent selectivity.Clean regiocontrol of the reaction is observed in the methylation of ethyl exo-6-(trans-1-propenyl)-2-oxobicyclo(3.1.0>hexane-1-carboxylate with trimethylaluminium or tetramethyl aluminiumlithium.Alkylation with trimethylaluminium proceeds with 86percent inversion of the configuration at C(6) of the substrate, affording (2R*,3R*)-2-ethoxycarbonyl-3-cyclopentanone which is transformed into neonepetalactone.