142096-79-5

Upstream product

• 75-11-6 diiodomethane 
• 75553-23-0 (E)-5-phenyl-2-penten-1-ol 
• 14399-53-2 bis(iodomethyl)zinc 
• 167482-48-6 1,2-O-Isopropylidene-3-O-(p-phenylbenzyl)-4,5-O-<(1'R)-trans-5'-phenyl-2'-penten-1'-yl>-β-D-fructopyranose 
• 167482-59-9 trans-5-Phenyl-2-penten-1-al diethyl acetal 
• 55282-95-6 ethyl (2E)-5-phenylpent-2-enoate 
• 33046-84-3 (2E)-5-phenyl-2-pentenal 
• 122-97-4 3-Phenyl-1-propanol 
• 104-53-0 3-phenyl-propionaldehyde 

Relevant academic research and scientific papers

Chiral recyclable fluorous disulfonamide ligand for catalytic enantioselective cyclopropanation of allylic alcohols

Allylic alcohols reacted with Et2Zn and CH2I2 in the presence of a catalytic amount of fluorous disulfonamide 3a to afford the corresponding cyclopropylmethanols in 69%-quantitative yields with 49-85% ee. Recovery of the fluorous ligand 3a was readily performed from the reaction mixture by the fluorous solid-phase extraction (FSPE), and the recovered 3a could be reused without a significant loss of the catalytic activity and enantioselectivity.

Highly efficient asymmetric simmons-smith cyclopropanation promoted by chiral heteroorganic aziridinyl ligands

Enantiomerically pure heteroorganic catalysts, bearing a hydroxy moiety, a stereogenic sulfinyl group, and a chiral aziridine moiety, have proved highly efficient in the asymmetric Simmons-Smith cyclopropanation of allylic alcohols, which generates the desired products in high yields (up to 95 %) and with ee values up to 94 %. The effect of the stereogenic centers at the sulfinyl sulfur atom and in the aziridine moiety on the stereochemical course of the title reaction is discussed. Combination at its best: Enantiomerically pure heteroorganic ligands, bearing a hydroxy moiety, a stereogenic sulfinyl group, and an enantiomeric aziridine moiety, have proved highly efficient in the asymmetric Simmons-Smith cyclopropanation of allylic alcohols, which generates the desired products in high yields (up to 95 %) and with ee values up to 94 %.

Catalytic enantioselective cyclopropanation of allylic alcohols using recyclable fluorous disulfonamide ligand

Cyclopropanation of allylic alcohols with Et2Zn and CH2I2 in the presence of a catalytic amount of fluorous disulfonamide 3 afforded the corresponding cyclopropylmethanols in 69-96% yield with 49-83% ee. The fluorous ligand 3 was readily recovered from the reaction mixture by the fluorous solid-phase extraction (FSPE) and could be reused without a significant loss of the catalytic activity and enantioselectivity.

Asymmetric Simmons-Smith reaction of allylic alcohols with Al Lewis acid/N Lewis base bifunctional Al(salalen) catalyst

(Chemical Presented) Three angles: A highly enantioselective Simmons-Smith reaction of trans-disubstituted allylic alcohols was achieved by using a catalytic amount of an Al(salalen) complex at room temperature (see scheme).

Catalytic asymmetric cyclopropanation of allylic alcohols with titanium-TADDOLate: Scope of the cyclopropanation reaction

A substoichiometric amount of titanium-TADDOLate complex was effective at catalyzing the cyclopropanation reaction of allylic alcohols in the presence 1 equiv of bis(iodomethyl) zinc. After initial optimization of the catalyst structure, excellent yields and enantiomeric ratios were obtained for 3-aryl- or 3-heteroaryl-substituted allylic alcohols (up to 97:3). Alkyl-substituted allylic alcohols gave modest yields and enantiomeric ratios (up to 87:13) but these compare favorably with those observed with other substoichiometric chiral ligands. The full synthetic scope of the reaction is presented in this paper.

Enantioselective cyclopropanation of allylic alcohols with dioxaborolane ligands: Scope and synthetic applications

A very effective chiral controller has been found for the conversion of allylic alcohols into the corresponding enantiomerically enriched cyclopropanes using bis(iodomethyl)zinc. A variety of chiral, nonracemic cyclopropylmethanols could be obtained according to this method. This methodology was extended with success to the cyclopropanation of unconjugated and conjugated polyenes and homoallylic alcohols. The cyclopropanation of allylic carbamates has also been investigated with this system, but it was found that enantioenriched cyclopropylmethylamines are best prepared from enantioenriched cyclopropylmethanols.

A new chiral disulfonamide ligand derived from α-amino acid for catalytic enantioselective cyclopropanation

A new disulfonamide prepared from α-amino acid in five steps catalyzed cyclopropanation of allylic alcohols with Et2Zn and CH2I2 to afford the corresponding cyclopropylmethanols in moderate to good enantioselectivites. In particular, the reaction of cinnamyl alcohol in the presence of a chiral disulfonamide 1k afforded an excellent enantioselectivity (85% ee).

Catalytic, Enantioselective Cyclopropanation of Allylic Alcohols. Substrate Generality

Catalytic, enantioselective cyclopropanation of a broad range of allylic alcohols and one homoallylic alcohol was carried out. The cyclopropanation reagent employed was bis(iodomethyl)zinc generated by the method of Furukawa, and the chiral promoter used (10 mol %) was the N,N-bis-(methanesulfonyl) derivative of (R,R)-1,2-diaminocyclohexane. Three experimental features were found to be critical for the rapid and selective cyclopropanation: (1) use of the ethylzinc alkoxide of the allylic alcohol as the substrate by prior deprotonation of the allylic alcohols by diethylzinc, (2) the formation of the zinc complex of the promoter by prior deprotonation of the bis-sulfonamide with diethylzinc, and (3) the use of added zinc iodide generated in situ from diethylzinc and iodine. The stereoselectivity of cyclopropanation was found to be independent of olefin geometry and worked well for substrates bearing both aliphatic and aromatic substituants at either or both 3-positions of the allylic alcohol. However, a methyl substituent on the 2-position of the allyl alcohol was not well tolerated and led to slow reactions and poor enantioselectivities. A rationale for the observed selectivities is proposed.

N,N,N′,N′-Tetraalkyl-2,2′-dihydroxy-1,1′- binaphthyl-3,3′-dicarboxamides: Novel Chiral Auxiliaries for Asymmetric Simons-Smith Cyclopropanation of Allylic Alcohols and for Asymmetric Diethylzinc Addition to Aldehydes

The newly introduced tittle compounds were found to be efficient chiral auxiliaries for the asymmetric Simmons-Smith cyclopropanation of allylic alcohols and for asymmetric addition of diethylzinc to aldehydes. For example, Simmons- Smith cyclopropanation of cinnamyl alcohol in the presence of N,N,N′,N′-tetraethyl-2,2′-dihydroxy-1, 1′-binaphthyl-3, 3′-dicarboxamide (1b) proceeded with high enantioselectivity of 94% ee and addition of diethylzinc to benzaldehyde in the presence of N,N,N′,N′-tetraisopropyl-2,2′-dihydroxy-1,1′-binaphthyl- 3,3′-dicarboxamide (1e) proceeded with enantioselectivity of 99% ee. Although the reaction mechanism of these reactions is still nuclear, a monomeric seven-membered 2,2′-dihydroxy-1,1′-binaphthyl-3,3′-dicarboxamide (1)-Zn complex is considered to be an active species which catalyzes the above reactions, on the basis of NMR experiments.

Asymmetric Cyclopropanation Using New Chiral Auxiliaries Derived from D-Fructose

Acetals of α,β-unsaturated aldehydes with 3-O-alkylated derivatives of 1,2-O-isopropylidene-β-D-fructopyranose and 1,2-O-isopropylidene-β-D-psicopyranose, which are readily available from D-fructose, were cyclopropanated with Et2Zn and CH2I2 with good diastereoselectivity.The effects of structure of the acetals on enantioselectivity were examined.