Peterson Olefination Reaction Research Articles

Novel Synthesis of Trisubstituted Olefins for the Preparation of the C16-C30 Fragment of Dolabelide C.

A silicon-tether ring-closing metathesis strategy is reported for the synthesis of trisubstituted olefins flanked by allylic or homoallylic alcohols, which are difficult to obtain by classical ring-closing or cross-metathesis reactions. In addition, a novel Peterson olefination reaction has been developed for the preparation of the allyldimethylsilane precursors, which are versatile synthetic intermediates. This method was then applied to the synthesis of the C16-C30 fragment of dolabelide C.

Synthesis of novel α-acyloxycarboxamides containing vinylbis(silanes) through three-component Passerini reactions

A three-component efficient procedure is described for the synthesis of novel α-acyloxycarboxamides containing bis(trimethylsilyl)ethenyl group from 4-[2,2-bis(trimethylsilyl)ethenyl]benzaldehyde, aromatic carboxylic acids and isocyanides, via the Passerini reaction. This reaction proceeds smoothly and cleanly under mild conditions in H2O and [bmim]BF4 at room temperature and led to products in good yields. The silylated aldehyde was obtained via Peterson olefination reaction of terephthalaldehyde with tris(trimethylsilyl)methyllithium in THF at 0 °C.

ChemInform Abstract: General Ambient Temperature Benzylic Metalations Using Mixed‐Metal Li/K‐TMP Amide.

AbstractUsing in‐situ prepared LiNK reagent, methylarenes are sequentially converted into mono‐ and bis‐trimethylsilylated derivatives.

N-heterocyclic carbene-catalysed Peterson olefination reaction

N-heterocyclic carbenes (NHCs) have been utilised as highly efficient organocatalysts to catalyse Peterson olefination reaction of aldehydes with trimethylsilylketene ethyl trimethylsilyl acetal or fluoro(trimethylsilyl)ketene ethyl trimethylsilyl acetal to produce the corresponding functionalized olefines in 34–93% yields with excellent stereoselectivities.

General Ambient Temperature Benzylic Metalations Using Mixed-Metal Li/K-TMP Amide.

Highly regioselective benzylic metalations in hydrocarbon solvent have been achieved at rt and 0 °C using a mixed-metal Li/K-TMP amide comprised of KOtBu, BuLi, and 2,2,6,6,-tetramethylpiperidine (TMP(H)). Mixing of KOtBu, BuLi, and TMP(H) in heptane gave a solution of the base mixture which when used in deuterium labeling experiments confirmed the requirement of the three reagent components for both reactivity and selectivity. The reaction protocol is operationally straightforward and found to be applicable to a broad range of substrates. Upon generation of the metalated products, they are reacted in heptane at ambient temperature in a variety of synthetically useful ways. Illustrated examples include generation of the benzyltrimethylsilanes and α,α-bis(trimethylsilyl)toluenes reagents, which are bench-stable surrogates of benzyl anions and α-silyl carbanions utilized for nucleophilic addition and Peterson olefination reactions. Direct C-C couplings mediated by 1,2-dibromoethane provided entries into bibenzyls and [2.2]metacyclophanes. Comparison of reaction outcomes with the same reactions carried out in THF at -78 °C showed no negative effects for conducting the reactions under these milder more user-friendly conditions.

Synthesis of novel dithiocarbamyl-containing organosilicon compounds

Aldehydes-bearing dithiocarbamate moieties were generated via highly efficient and simple method based on the one-pot reaction of amines, CS2, and 4-(bromoalkoxy)benzaldehydes with the use of K2CO3 as a catalyst under solvent-free conditions. The mild reaction conditions, high yields, and broad scope of the reaction, illustrate the good synthetic utility of this method. The newly synthesized aldehydes were converted to 1,1-bis(trimethylsilyl)-1-alkenes via the Peterson olefination reaction and produced dithiocarbamate-based organosilane compounds.

Synthesis of 2-aryl-1,1-Bis(Silyl)Alkenes-Containing Tetrasubstituted Imidazoles Catalysed by M–Cu/ZSM-5 (M: Cr, Mn, Co, Ni, V, Zn and Fe) Zeolites-Supported Bimetallic Nanostructures

The one-pot synthesis of tetrasubstituted imidazoles by using a series of M-Cu/ZSM-5 (M: Cr, Mn, Co, Ni, V, Zn and Fe) zeolites-supported bimetallic catalysts was studied. Fe-Cu/ZSM-5 bimetallic oxide catalyst had the highest activity in improving the efficiency of the heterogeneous cyclo-condensation reaction. Some imidazole derivatives terminated by vinylbis(silanes) have been synthesised using (Me3Si)3CLi through the Peterson olefination reaction.

Synthesis of 2-Aryl-1,1-Bis(Silyl)Alkenes Containing Alkyl(Aryl)Amine Groups

4-Alkyl-(aryl)aminobenzaldehydes have been generated via the nucleophilic aromatic substitution reaction of 4-fluorobenzaldehyde with appropriated amines and N-heterocycles using hexadecyltrimethylammonium bromide as catalyst and converted to 1,1-bis(silyl)-1-alkene derivatives via the Peterson olefination reaction. The reaction of (HMe2Si)3CLi with these aromatic aldehydes led to new 2-aryl-1,1-bis(silyl)alkenes.

Peterson Olefination: Unexpected Rearrangement in the Overcrowded Polycyclic Aromatic Ene Series

AbstractAn attempted synthesis of the angularly annelated 9‐(11′‐benzo[a]fluoren‐11′‐ylidene)‐9H‐fluorene (3) through a Peterson olefination reaction between (9H‐fluoren‐9‐yl)trimethylsilyl anion (5a) and 11H‐benzo[a]fluoren‐11‐one (6) led to the linearly annelated 9‐(11′‐benzo[b]fluoren‐11′‐ylidene)‐9H‐fluorene (4), due to an unexpected rearrangement. The proposed mechanism of the rearrangement is illustrated. The core of the mechanism is an intramolecular Haller–Bauer cleavage of the naphthyl C11a′–C11′ bond in the β‐oxysilane anion 11 (formed from 5a and 6) to give the 1‐naphthyl anion (E)‐12, followed by E/Z isomerization to (Z)‐12 and by proton migration to give the 3‐naphthyl anion (Z)‐14. The intramolecular nucleophilic addition of the naphthyl anion at C‐3′ of (Z)‐14 to the carbonyl carbon gives the β‐oxysilane anion 15, a benzo[b]fluorenylidene derivative. The mechanism is supported by the results of DFT calculations. The synthesis of 3 was achieved by application of Barton's double extrusion diazo–thione coupling method.

Synthesis of new imines and amines containing organosilicon groups

The Peterson olefination reaction of terephthalaldehyde with tris(trimethylsilyl)methyl lithium, (Me 3Si) 3CLi, in THF at 0 °C gives 4-[2,2-bis(trimethylsilyl)ethenyl]benzaldehyde ( 1) and 4,4-bis[2,2-bis(trimethylsilyl)ethenyl]benzene ( 2). The new aldehyde ( 1) reacts with variety of amines in ethanol to afford the corresponding imines ( 3) containing vinylbis(trimethylsilyl) group. The newly synthesized imines ( 3) can be completely converted into amines containing vinylbis(trimethylsilyl) group with an excess amount of NaBH 4. In the case of N-[4-(2,2-bis(trimethylsilyl)ethenyl)benzyl]-2,6-dimethylaniline LiAlH 4 was used as a reducing agent in THF.

ChemInform Abstract: The Stereoselective Construction of Z-3-Aryl-2-fluoroalkenoates.

The use of 2,4,6-trimethylphenyl α-silyl-α-fluoroacetate in the Peterson olefination reaction leads to the highly stereoselective formation of (Z)-3-aryl-2-fluoroalkenoates via an aldol reaction most likely proceeding through an open transition state since stereocontrol of the enolate geometry was not possible

ChemInform Abstract: A Peterson Olefination Reaction Using Silyl-Substituted Sulfonamide Carbanions. Synthesis of Vinylic Sulfonamides.

Abstract α-Trimethylsilyl-substituted sulfonamides RCH(SiMe3)SO2N(CH3)2 (3), (R[dbnd]H, CH3 and C6H5) are synthetized in almost quantitative yields. Their lithium derivatives 4 undergo a smooth Peterson olefination reaction with nonenolisable carbonyl compounds to give good to excellent yields of vinylsulfonamides 6. With R[dbnd]H, the reaction is highly E-stereoselective. Moderate stereoselectivity is obtained in the cases of R[dbnd]CH3 and R[dbnd]C6H5.

ChemInform Abstract: Stereoselective Synthesis of (E)- and (Z)-2-Alkenyltrimethylsilanes from 1,2-Epoxy-1,3-bis(trimethylsilyl)propane.

Stereoselective synthesis of various (E)- and (Z)-2-alkenyltrimethylsilanes (RCH=CHCH2SiMe3; R=Me, Et, n-Bu, i-Pr, c-hexyl, t-butyl, and phenyl) has been accomplished by a reaction of 1,2-epoxy-1,3-bis(trimethylsilyl)propane with Grignard reagents (RMgX) followed by subsequent Peterson olefination reactions of resulting 1,2-bis(trimethylsilyl)-3-alkanols [RCH(OH)CH(SiMe3)CH2SiMe3]; the acid (BF3OEt2 or HClO4)-catalyzed olefination yields the (E)-isomer, while the base (KH or NaH)-induced olefination yields the (Z)-isomer in more than 95% stereochemical purity in most cases.

ChemInform Abstract: Synthesis and Rearrangement of Dispiro Epoxy β-Lactams.

Abstract α-Methylene-β-lactams are prepared by a Peterson olefination reaction. These substrates can be epoxidized with MCPBA to give the title dispiro-epoxy-β-lactams. Under the influence of boron trifiuoride, these substrates rearrange to spiro-3-ketolactams.

Synthesis, characterization and thermal behaviors of polymers containing organosilicon groups

Various bis(silyl)ethenyl groups were attached to the aromatic ring of poly(α-methylstyrene) via Peterson olefination reaction of (RMe2Si)3CLi (R = H, Me and Ph) with formylated poly(α-methylstyrene) (Pα-MS-CHO) to give poly(α-methylstyrene)-co-[2,2-bis(silyl)ethenyl(α-methylstyrene)] as functionalized poly(α-methylstyrene) (Pα-MS-SiMe2H, Pα-MS-SiMe3 and Pα-MS-SiMe2Ph). The trimethylsilyl groups of Pα-MS-SiMe3 have been converted to 2,2-dibromoethenyl and epoxybis(silanes) groups via NBS-based bromodesilylation and MCPBA-based epoxidation respectively. The thermal degradation behaviors of the polymers were studied using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC).

1,4-bis[2,2-bis(trimethylsilyl)ethenyl]benzene: Regioselective ring opening of its α,β-epoxybis(silane) with some nucleophiles

Abstract The Peterson olefination reaction of terephthalaldehyde with tris(trimethylsilyl)methyllithium, (Me3Si)3CLi, in Et2O gives disubstituted vinylbis(silane) 1 which reacts with MCPBA in CH2Cl2 at r.t. to afford mixture of mono and disubstituted epoxybis(silanes) 3 and 2. Vinylbis(silane) 1 can be completely converted into epoxybis(silane) 2 with an excess amount of MCPBA. The compound 2 was reacted with various reagents such as HX (X = Cl, Br), H2SO4, LiAlH4 and MeLi/CuI and give the related products.

The conjugate addition–Peterson olefination reaction for the preparation of cross-conjugated cyclopentenone, PPAR-γ ligands

5-Alkylidenecyclopent-2-enones 15a-q may be prepared via a conjugate addition-Peterson olefination sequence, best achieved in one-pot, using exo-2-trimethylsilyl-3a,4,7,7a-tetrahydro-4,7-methanoinden-1-one 12, followed by a retro-Diels-Alder reaction. The geometry of the exocyclic alkene may be controlled according to the use of organometallic species in the conjugate addition step; organocuprate reagents are found to selectively lead to the formation of E-exocyclic alkene adducts, whereas Grignard reagents favour the formation of Z-alkenyl isomers. The use of enantiomerically enriched 12, accessed from an asymmetric Pauson-Khand reaction, affords the corresponding enantioenriched 5-alkylidenecyclopent-2-enones and this approach is exemplified by the short, stereoselective total syntheses of two cyclopentenone phytoprostanes 51 and 13,14-dehydrophytoprostane J1 65. The ability of this family of synthetic compounds to activate the peroxisome proliferator activated receptor-gamma is reported.

Total Synthesis of (+)‐Dactylolide Through an Efficient Sequential Peterson Olefination and Prins Cyclization Reaction.

Total Synthesis of (+)‐Dactylolide Through an Efficient Sequential Peterson Olefination and Prins Cyclization Reaction.

Total Synthesis of (+)‐Dactylolide through an Efficient Sequential Peterson Olefination and Prins Cyclization Reaction

Total Synthesis of (+)‐Dactylolide through an Efficient Sequential Peterson Olefination and Prins Cyclization Reaction

Total Synthesis of (+)‐Dactylolide through an Efficient Sequential Peterson Olefination and Prins Cyclization Reaction

Total Synthesis of (+)‐Dactylolide through an Efficient Sequential Peterson Olefination and Prins Cyclization Reaction