26429-96-9

Upstream product

• 104-53-0 3-phenyl-propionaldehyde 
• 88738-78-7 bis-(2,2,2-trifluoroethyl)(methoxycarbonylmethyl)phosphonate 
• 1779-58-4 (methyloxycarbonylmethyl)triphenylphosphonium bromide 
• 1529-78-8 [(methoxycarbonyl)methyl]triphenylarsonium bromide 
• 21204-67-1 methyl (triphenylphosphoranylidene)acetate 
• 1067-74-9 Methyl diethylphosphonoacetate 
• 5927-18-4 trimethyl phosphonoacetate 
• 18328-11-5 3-benzyl propionaldehyde 
• 96-32-2 bromoacetic acid methyl ester 

Downstream Products

• 14983-20-1 (+/-)-methyl 3-methyl-5-phenylpentanoate 
• 99439-81-3 (-)-methyl 3-methyl-5-phenylpentanoate 
• 33599-84-7 methyl (E)-5-phenyl-4-pentenoate 
• 39520-63-3 (Z)-5-phenylpent-2-en-1-ol 

Relevant academic research and scientific papers

Trifluoromethylation of Unactivated Alkenes with Me3SiCF3 and N-Iodosuccinimide

A novel approach to the trifluoromethylation of unactivated alkenes is presented. This reaction is promoted by N-iodosuccinimide (NIS) under visible light irradiation without the need for photocatalysts. The mild conditions allow the direct synthesis of u

Synthesis and evaluation of (E)-2-(5-phenylpent-2-en-4-ynamido)cyclohex-1-ene-1-carboxylate derivatives as HCA2 receptor agonists

Novel series of compounds consisting of 2-amidocyclohex-1-ene carboxylate and phenyl parts which are connected by enyne (compounds 2a–f), but-1-yne (compounds 4a–j), and phenylethylene (compounds 5a–f) linkers as HCA2 full agonists were designed and their

Phospholane-catalyzed wittig reaction

We identified 2-phenylisophosphindoline 2-oxide as a suitable and potentially tunable catalyst for the catalytic Wittig reaction of aldehydes with activated organohalides. This catalyst was obtained by a straightforward two-step synthesis. Trimethoxysilane proved to be an efficient reducing agent for the in situ generation and regeneration of the catalyst from the corresponding phosphane oxide. Sodium carbonate was identified as a suitable base for the transformation. It is noteworthy that the particle size of the sodium carbonate had a tremendous effect on the outcome of the reaction. Under the optimized reaction conditions, 23 aldehydes were converted into the corresponding alkenes in high isolated yields of up to 88%. Moreover, an asymmetric catalytic Wittig reaction was performed for the desymmetrization of a prochiral diketone.

Scope and Limitation of the Microwave-Assisted Catalytic Wittig Reaction

We have developed a microwave-assisted catalytic Wittig reaction. In this paper, we give full account of the scope and limitations of this reaction. A screening of various commercially available phosphine oxides as precatalysts revealed Bu3P=O to be the most promising candidate. We tested 10 silanes for the in situ reduction of the phosphine oxide to generate Bu3P as the actual catalyst. Different epoxides were tested as masked bases. In this context, cyclohexene oxide as well as butylene oxide proved to be suitable. The reaction could be carried out at 125 C, but higher yields and E/Z selectivities were obtained at 150 °C. Under the optimised reaction conditions, more than 40 examples for the conversion of various aldehydes into the corresponding alkenes are reported. The products were obtained in yields of up to 88 with high E selectivities. Moreover, we also describe the further screening of several chiral phosphines as catalysts for the microwave-assisted enantioselective catalytic Wittig reaction. The scope and limitations of the microwave-assisted catalytic Wittig reaction have been evaluated with respect to the catalyst, silane, solvent, reaction conditions, and substrates.

First Microwave-Assisted Catalytic Wittig Reaction

We introduce a novel catalytic Wittig reaction based on an inexpensive and readily available phosphane oxide as a precatalyst. The performance of the reaction under microwave irradiation led to significantly improved yields and reaction rates relative to those obtained under conventional heating. Moreover, herein we enclose the first example of the asymmetric catalytic Wittig reaction based on a chiral phosphane as the catalyst.

The asymmetric aza-claisen rearrangement: development of widely applicable pentaphenylferrocenyl palladacycle catalysts

Systematic studies have been performed to develop highly efficient catalysts for the asymmetric aza-Claisen rearrangement of trihaloacetimidates. Herein, we describe the stepwise development of these catalyst systems involving four different catalyst generations finally resulting in the development of a planar chiral pentaphenylferrocenyl oxazoline palladacycle. This complex is more reactive and has a broader substrate tolerance than all previously known catalyst systems for asymmetric aza-Claisen rearrange-ments. Our investigations also reveal that subtle changes can have a big impact on the activity. With the enhanced catalyst activity, the asymmetric aza-Claisen rearrangement has a very broad scope: the methodology not only allows the formation of highly enantioenriched primary allylic amines, but also secondary and tertiary amines; al-lylic amines with N-substituted quaternary stereocenters are conveniently accessible as well. The reaction conditions tolerate many important functional groups, thus providing stereoselective access to valuable functionalized building blocks, for example, for the synthesis of unnatural amino acids. Our results suggest that face-selective olefin coordination is the enantioselectivitydetermining step, which is almost exclusively controlled by the element of planar chirality.

Highly (E)-selective wadsworth-emmons reactions promoted by methylmagnesium bromide

(Chemical Equation Presented) An experimentally simple protocol for the very highly (E)-selective Wadsworth-Emmons reaction [(E):(Z) selectivities in excess of 180:1 in some cases] of a range of straight-chain and branched aliphatic, substituted aromatic, and base-sensitive aldehydes via reaction with an alkyl diethylphosphonoacetate and MeMgBr is reported.

Synthesis of optically active β-alkyl aspartate via [3,3] sigmatropic rearrangement of α-acyloxytrialkylsilane

The synthesis of four types of optically active β-carbon-substituted analogs of threo-β-hydroxy aspartate (THA) and a β-carbon-substituted analog of threo-β-benzyloxy aspartate (TBOA), which are potent blockers of excitatory amino acid transporters in the

Stereoselective aldol reaction of α-seleno carbonyl compounds: Preparation of (Z)-α,β-unsaturated carbonyl compounds

The aldol reaction of the titanium enolates of α-seleno esters in the presence of Ph3P or Ph3PO gave the products with high stereoselectivity favoring the syn isomers. Reaction of α-seleno ketones with TiCl4 in the presence of 2 equiv. of Et3N, and subsequently with aldehydes, gave the aldol products with high syn selectivity. The stereoselectivity in the aldol reaction of 3-pentanone also increased by using an excess amount of Et3N. The aldol products thus obtained from the α-seleno carbonyl compounds could be stereospecifically converted to (Z)-α,β-unsaturated carbonyl compounds by treatment with pyridine. (Z)-Alkylidenecyclopentanones were exclusively formed by treatment of the syn-aldol products with Et3N in the dark.

The reaction of triphenylphosphonium or triphenylarsonium salts with aldehyde: Effect of the counteranion on their reactivity

Some acetonyltriphenylphosphonium, methoxycarbonylmethyltriphenylphosphonium salts and their triphenylarsonium analogues could undergo Wittig reaction with aldehyde in good yields. Their reactivity was counteranion-dependent and was arranged in the following order: p-TsO-, Br-3CO2/-2CO2/-2/-, HCO2/-, MeCO2/-. The proton-coupled 13C NMR splitting patterns of the α-methylene groups provided a valuable information to predict their reactivity with aldehyde. Only those onium salts without C-H coupling could undergo Wittig reaction. (C) 2000 Elsevier Science Ltd.