7302-03-6

Upstream product

• 772-46-3 2-methyl-1-phenyl-2-butanol 
• 6228-47-3 n-propyltriphenylphosphonium bromide 
• 100-52-7 benzaldehyde 
• 74-88-4 methyl iodide 
• 13384-54-8 (Z)-(2-methylbut-1-en-1-yl)benzene 
• 121368-72-7 erythro-2-Ethyl-3-hydroxy-2-methyl-3-phenylpropionic Acid 
• 21481-98-1 sec-butylidene-triphenyl-λ⁵-phosphane 
• 121368-72-7 2-Ethyl-3-hydroxy-2-methyl-3-phenylpropanoic acid 
• 121368-72-7 Erythro 2-Ethyl-3-hydroxy-2-methyl-3-phenylpropanoic acid 
• 121368-72-7 threo-2-Ethyl-3-hydroxy-2-methyl-3-phenylpropanoic acid 
• 7555-67-1 1-phenylmethylenecyclopropane 
• 77-78-1 dimethyl sulfate 
• 14198-15-3 Methyl-(3-phenyl-2-ethyl-propyl)-sulfoxid 
• 673-32-5 1-Phenylprop-1-yne 

Downstream Products

• 13384-54-8 (Z)-(2-methylbut-1-en-1-yl)benzene 

Relevant academic research and scientific papers

Preparation and reactions of monocyclic bis(cyclopentadienyl)titanacyclopentenes and -pentadienes

A combination of Cp2TiCl2-2EtMgBr was found to be very effective for the formation of monocyclic titanacyclopentenes in excellent yields. On the other hand, a combination of Cp2TiCl2-2n-BuLi was used for intermolecular coupling of two alkynes to form titanacyclopentadienes in good to excellent yields. A reaction temperature range from -10 to -30°C was critical for the success of the combinations. Reactions of these in situ-prepared titanacycles show interesting similarities to or differences from their zirconacycle analogs.

A Nickel-catalyzed carbozincation of aryl-substituted alkynes

The addition of dialkylzincs or diphenylzinc to substituted phenylacetylenes in the presence of catalytic amounts of Ni(acac)2 in THF:NMP mixtures produces syn-carbozincation products with good to excellent regio- and stereoselectivity. After quenching with an electrophile (iodine, acyl chloride, allyl bromide) tetrasubstituted olefines are obtained in good to satisfactory yields. An intramolecular version of the reaction is possible using a terminal triple bond bearing an iodine at a remote position. More substituted iodo-alkynes furnish only reductive elimination products. An application to a stereoselective synthesis of (Z)-tamoxifen (Z:E > 99:1) has been developed.

New nickel-catalyzed carbozincation of alkynes: A short synthesis of (Z)-tamoxifen

A new highlight in the repertoire of carbometalation reactions is the highly stereo- and regioselective nickel-catalyzed carbozincation of internal alkynes. This is exemplified by a short and effective synthesis of the anti-breast-cancer drug (Z)-tamoxifen. This reaction also allows the stereoselective synthesis of various tri- and tetrasubstituted olefins in good yield.

Radical-Stabilization-Energy - the MMEVBH Force Field

Making use of the VB method of Malrieu et al. a force field has been developed, which allows to calculate heats of formation of hydrocarbons (conjugated and non-conjugated olefins, radicals and diradicals) with high accuracy.With this method radical stabilization energies (RSE) for a great number of delocalized radicals are calculated and compared with experimental values, derived from shock-tube measurements of dissociation energies or from rotational barriers of substituted olefins.A detailed analysis of the RSE with respect to structure, substituents, strain, and aromaticity is presented. - Key Words: Resonance energy / Heats of formation / Single pulse shock tube / Intrisic rotational barrier

Polylithiumorganic compounds -19. Regioselective carbon-carbon σ-bond scission followed by a 1,6-proton shift upon the reductive metalation of benzylidenecyclopropane derivatives with lithium metal

Depending on the substituent α-substituted benzylidenecyclopropanes (32) react more or less readily with lithium dust (2% sodium) in diethyl ether whereby a regioselective scission of only the cyclopropane σ-bond cis to the phenyl ring takes place. Upon raising the temperature the primarily formed 1,3-dilithiumorganic compound due to an agostic interaction rearranges by a 1,6-proton shift into a doubly bridged 1,4-dilithio compound. With α-methylbenzylidenecyclopropane (32c) this rearrangement was shown to occur intermolecularly via a trilithiumorganic compound 56. The suggested mechanism of these reductive metalation reactions via a bisected radical anion 87 where the lithium is mainly bound to the cyclopropyl carbon atom and oriented syn to the phenyl ring, was supported by MNDO (geometries) and ab initio (energies) calculations.

A Dynamic Equilibrium of Oxaphosphetanes

The course of the Wittig reaction was investigated by rapid injection NMR spectroscopy.Rate constants for the formation of oxaphosphetanes were determined.A new dynamic equilibrium of oxaphosphetanes was observed for the first time.The solvent and substituent dependence of the new effect was investigated.By labeling various oxaphosphetanes with 13C and 17O the lithium salt dependence of the new equilibrium was shown.A lithium adduct of oxaphosphetanes under these conditions is proposed. - Key Words: Wittig reaction / Rapid injection NMR / Dynamic NMR / Oxaphosphetanes

Olefin Synthesis by Vanadium(V)-Induced Oxidative Decarboxylation-Deoxygenation of 3-Hydroxy Carboxylic Acids

Oxidative decarboxylation of 3-hydroxy carboxylic acids can be effected with various V(V) complexes.This process likely yields an intermediate 1,4-metalla diradical. β-elimination from this intermediate gives olefin and regenerates V(V), likely as VO2Cl.Thus, although the overall process involves no net change in oxidation state for vanadium, the decarboxylation process is oxidatively induced.Intramolecular trapping of the intermediate yields glycolate and then C-C cleavage products, and skeletal rearrangement gives ketonic products.Qualitatively, rates for oxidative decarboxylation of the acids and the stereospecificity of formation of olefinic products depend on the electron-withdrawing ability of groups attached to vanadium.Methodology is described for the preparation of tri- and tetrasubstituted olefins in high yield from appropriate 3-hydroxy carboxylic acid precursors.

Differential NMR Shielding by Phenyl, Assigned from Chemical Labelling and (Z,E) Equilibration

Unequivocal NMR assignments of the (E,Z) isomeric pairs 3 and 8 are possible by (Z,E) equilibration.Deprotonation of 2-methyl-1-phenylpropene (1) with n-BuLi under any conditions gives only a single allyl-metal derivative 2.Methylation of the latter gives

OLEFIN SYNTHESIS VIA THE LITHIUM DERIVATIVE OF THE N,N,N',N'-TETRAMETHYLDIAMIDES OF ARYLMETHANEPHOSPHONIC ACIDS. 3. SYNTHESYS OF SOME β-DISUBSTITUTED STYRENES

The reaction of Li-derivatives of N,N,N',N'-tetramethyldiamides of arylmethanephosphonic acids (1-Li) with alkanones, cycloalkanones, alkylaryl- and diarylketones 2a-h is studied.It is found that in THF at -70 deg C adducts 3-Li and 4-Li are formed, the corresponding hydroxyl compounds 3 and 4 being isolated in 36-81percent yields, while by elevated temperatures the reaction is completely shifted to the starting 1-Li and 2.By thermolysis of 3 and 4 in neutral medium olefins 5 and 6 are obtained even from readily enolysable ketones.The stereochemistry of the addition reaction with nonsymmetrical ketones as well as the influence of the substituents at the carbonyl groups on the conformation and adsorption properties of the adducts are discussed.