1647-06-9

Usage

Synthesis Reference(s)

The Journal of Organic Chemistry, 47, p. 4482, 1982 DOI: 10.1021/jo00144a016

InChI:InChI=1/C11H14/c1-3-10(2)9-11-7-5-4-6-8-11/h3-8,10H,1,9H2,2H3

Upstream product

• 590-18-1 (Z)-2-Butene 
• 908094-04-2 phenyldiazomethane 
• 78-79-5 isoprene 
• 1666-17-7 benzaldehyde p-toluenesulfonylhydrazone 
• 628-08-0 crotyl acetate 
• 5281-18-5 benzaldehyde, hydrazone 
• 6737-11-7 2-acetoxy-3-butene 
• 768-56-9 4-Phenylbut-1-ene 
• 917-64-6 methyl magnesium iodide 
• 100-52-7 benzaldehyde 
• 5445-77-2 2-benzylpropionaldehyde 
• 27200-84-6 methyl triphenylphosphonium bromide 
• 83565-90-6 C₁₇H₁₉NO₃S 
• 17322-34-8 (2-nitropropyl)benzene 

Downstream Products

• 103-82-2 phenylacetic acid 
• 53774-20-2 2-methylbut-3-enoic acid 

Relevant academic research and scientific papers

Controllable, Sequential, and Stereoselective C-H Allylic Alkylation of Alkenes

The direct conversion of C-H bonds into new C-C bonds represents a powerful approach to generate complex molecules from simple starting materials. However, a general and controllable method for the sequential conversion of a methyl group into a fully substituted carbon center remains a challenge. We report a new method for the selective and sequential replacement of three C-H bonds at the allylic position of propylene and other simple terminal alkenes with different carbon groups derived from Grignard reagents. A copper catalyst and electron-rich biaryl phosphine ligand facilitate the formation of allylic alkylation products in high branch selectivity. We also present conditions for the generation of enantioenriched allylic alkylation products in the presence of catalytic copper and a chiral phosphine ligand. With this approach, diverse and complex products with substituted carbon centers can be generated from simple and abundant feedstock chemicals.

Umpolung of Carbonyl Groups as Alkyl Organometallic Reagent Surrogates for Palladium-Catalyzed Allylic Alkylation

Palladium-catalyzed allylic alkylation of nonstabilized carbon nucleophiles is difficult and remains a major challenge. Reported here is a highly chemo- and regioselective direct palladium-catalyzed C-allylation of hydrazones, generated from carbonyls, as a source of umpolung unstabilized alkyl carbanions and surrogates of alkyl organometallic reagents. Contrary to classical allylation techniques, this umpolung reaction utilizes hydrazones prepared not only from aryl aldehydes but also from alkyl aldehydes and ketones as renewable feedstocks. This strategy complements the palladium-catalyzed coupling of unstabilized nucleophiles with allylic electrophiles by providing an efficient and selective catalytic alternative to the traditional use of highly reactive alkyl organometallic reagents.

Stereoselective synthesis of α-methyl and α-alkyl ketones from esters and alkenes: Via cyclopropanol intermediates

Alkenes bearing a stereocenter in the allylic position were found to undergo Kulinkovich hydroxycyclopropanation with good diastereoselectivity. For the isomerization of the resulting cyclopropanols to diastereomerically enriched α-methyl ketones, a new mild regioselective method has been developed. A sequence of stereoselective cyclopropanation and cyclopropanol ring opening was successfully employed for the construction of the C20 stereocenter in steroids.

Copper catalyzed magnesium-Barbier reaction for γ-selective alkyl-allyl coupling

CuCN catalyzed alkyl-allyl coupling under magnesium-Barbier conditions occurs regioselectively and affords predominantly the γ-products in good to high yields. This one-pot CuCN catalyzed reaction utilising Mg, an alkyl halide and an allylic substrate in THF at room temperature provides an easy alternative to the classical CuCN catalyzed γ-allylation of alkyl Grignard reagents.

Selective Deprotection of Acetals with Me3SiCH2MgCl. Peterson-Type Olefination of Acetals

By employing the chelation strategy, treatment of an acetal of a contiguous diol with Me3SiCH2-MgCl liberates the corresponding diol regioselectively. In addition, acetals of different structural variety are transformed upon treatment with Me3SiCH2MgCl and ZnI2 into the corresponding olefination products in good yield.

The regiochemistry of the protodesilylation of some cyclopropylmethylsilanes derived from allylsilanes

Simmons-Smith type methylenation of allylsilanes, followed by protodesilylation, can be used to achieve overall the S(E)2' replacement of the silyl group by a methyl group. The regioselectivity is good for protonation on the methylene carbon of the cyclopropylmethylsilanes 11, 17, 20 and 23, but the low stereoselectivity in the formation of the cyclopropylmethylsilane 26 and its failure to undergo clean protodesilylation make the method of limited use.

Regioselective Removal of Allylic Nitro Groups via Hydride Transfer

Allylic nitro groups are regioselectively removed by hydride-transfer reaction in the presence of a catalytic amount of a palladium catalyst

DENITROHYDROGENATION OF ALIPHATIC NITRO COMPOUNDS AND A NEW USE OF ALIPHATIC NITRO COMPOUNDS AS RADICAL PRECURSORS

Aliphatic nitro groups are replaced by hydrogen on treatment with tributyltin hydride which proceeds via free radical chain processes.As the nitro group is selectively denitrated and other reducible groups are not affected with tributyltin hydride, this reaction can be used as a method for removing the nitro group from polyfunctional compounds.The radical intermediates generated via denitration can be also used for the carbon-carbon bond forming reactions.

COMPLEXES OF TRANSITION METALS IN THE CHEMISTRY OF CONJUGATED SYSTEMS. III. REACTION OF DIENE HYDROCARBONS WITH ORGANOMAGNESIUM COMPOUNDS IN THE PRESENCE OF SALTS AND COMPLEXES OF TRANSITION METALS

The effect of the structure of the reagents and the nature of the catalyst on the direction and selectivity in the reaction of 1,3-dienes and their derivatives with aromatic Grignard reagents was investigated.It was shown that in the presence of salts and complexes of iron(III) 1,3-alkadienes R1CH=C(R2)C(R3)=CH2 react with arylmagnesium halides to form trans-(E)-1-aryl-1,3-alkadienes, whereas the sterically hindered (R2, R3=CH3) cyclic 1,3-alkadienes and also 1,2-alkadienes give mainly adducts (1:1).Catalysis by the phosphine complexes of nickel(II) leads to the formation of telomeric (2:1) (E)-1-aryl-2,7- and (E,E)-1-aryl-2,6-alkadienes.The results demonstrate the determining role of the stereochemical conditions for the coordination of the diene in the course of the reaction and also the significant contribution from the processes of one-electron reduction of the catalyst.

Selectivity in the Allylic Substitutions with Organometallics through Neighboring Coordination. 2-(Allyloxy)benzothiazoles as SN2' Electrophiles for Regio- and Stereoselective Olefin Syntheses

An efficient control of the regio- and stereochemistry in the allylic substitutions with organomagnesium compounds has been achieved by using 2-(allyloxy)benzothiazoles as substrates in the presence of copper bromide.The selectivity is due to the coordinative effects of the substrates toward the organometallic species.