4581-74-2Relevant academic research and scientific papers
A short asymmetric synthesis of (-)-neonepetalactone
Enders, Dieter,Kaiser, Anja
, p. 631 - 635 (2007/10/03)
(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).
Extracyclic Stereocontrol in Addition Reaction of Crotylsilanes with 2-Substituted 2-Cyclopentenones. Stereodivergent Synthesis of (+)-Neonepetalacton and (+)-Isoneonepetalactone
Pan, Li-Rui,Tokoroyama, Takashi
, p. 1999 - 2002 (2007/10/02)
The addition reaction of E- and Z-crotylsilanes with 2-substituted 2-cyclopentenones showed the preference of erythro and threo products respectively.The refinement of the selectivity was investigated and the result was utilized for efficient syntheses of
Reaction of Organoaluminium Reagents with Cyclopropylmethyl Acetates and 2-Vinylcyclopropane-1,1-dicarboxylate Esters
Hiyama, Tamejiro,Morizawa, Yoshitomi,Yamamoto, Hajime,Nozaki, Hitosi
, p. 2151 - 2160 (2007/10/02)
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.
REVISIONS OF THE ABSOLUTE CONFIGURATIONS OF C-8 METHYL GROUPS IN DEHYDROIRIDODIOL, NEONEPETALACTONE, AND MATATABIETHER FROM ACTINIDIA POLYGAMA MIQ
Sakai, Tsutomu,Nakajima, Kimiko,Yoshihara, Kazuo,Sakan, Takeo,Isoe, Sachihiko
, p. 3115 - 3119 (2007/10/02)
The absolute configurations of C-8 Me groups in dehydro-iridodiol, neonepetalactone, and matatabiether isolated from the cat- and lacewing-attracting plant Actinidia polygama Miq. were revised to the S configurations on the basis of chemical transformatio
