88089-52-5

Upstream product

• 451-40-1 phenyl benzyl ketone 
• 75-77-4 chloro-trimethyl-silane 
• 55409-09-1 1,2-dicyclohexyl-2-hydroxy-ethanone 
• 3289-28-9 ethyl cyclohexanecarboxylate 
• 1459-20-7 1,2-diphenyl-2-oxoethyl benzoate 
• 26205-39-0 1,2-diphenyl-2-(trimethylsilyloxy)ethanone 
• 205884-21-5 1,2-Dicyclohexyl-2-(p-tolylsulfonyloxy)ethanone 
• 115262-00-5 [chloro(difluoro)methyl]trimethylsilane 

Downstream Products

• 119-53-9 2-hydroxy-2-phenylacetophenone 
• 105597-93-1 (2,3-Diphenyl-oxiranyloxy)-trimethyl-silane 
• 63578-71-2 Thiophosphoric acid O,O'-diethyl ester S-(2-oxo-1,2-diphenyl-ethyl) ester 
• 447-31-4 Desyl chloride 
• 679799-65-6 3-hydroxy-1,2-diphenyl-4-nonyn-1-one 
• 451-40-1 phenyl benzyl ketone 
• 1816-89-3 2-azido-1-(1,2-diphenyl)ethanone 
• 1404225-02-0 methyl (S)-5-oxo-2,3-diphenylcyclopent-1-enecarboxylate 
• 1404225-01-9 methyl (4S,5S)-2-((tertbutyldimethylsilyl)oxy)-4,5-diphenyl-5-((trimethylsilyl)oxy)cyclopent-1-enecarboxylate 
• 720-43-4 2-fluoro-1,2-diphenylethanone 
• 679799-43-0 1,2-diphenyl-2-nonen-4-yn-1-one 
• 4057-61-8 3,4-diphenyl-1,2,5-thiadiazole 
• 5928-66-5 (R)-benzoin 
• 5928-67-6 (S)-(+)-benzoin 

Relevant academic research and scientific papers

Synthesis of α-Ketoimidoyl Fluorides via Geminal Fluorine-Promoted Azide Rearrangement

Despite the promising synthetic potential, the utilization of imidoyl fluorides has been hampered by the lack of broadly applicable preparative methods. Herein, bench-stable α-ketoimidoyl fluorides were synthesized from geminal chlorofluorides through tandem azidation/rearrangement under mild conditions. The efficiency was consistently high, regardless of the steric and electronic environments. The synthetic utility of the α-ketoimidoyl fluoride was also demonstrated. Furthermore, the remarkable accelerating effect of the geminal fluorine substituent was identified and rationalized by density functional theory calculation.

Halogenative difluorohomologation of ketones

A method for the difluorohomologation of ketones accompanied by halogenation of a C-H bond is described. The reaction involves silylation, difluorocarbene addition using Me3SiCF2Br activated by a bromide ion, and halogenation of intermediate cyclopropanes with N-bromo- or N-iodosuccinimide. The whole process is performed without isolation of intermediates. The resulting α,α-difluoro-β-halo-substituted ketones can be readily converted into fluorine containing pyrazole derivatives and oxetanes.

A convenient method for the preparation of α-vinylfurans by phosphine-initiated reactions of various substituted enynes bearing a carbonyl group with aldehydes

α-Vinylfurans were obtained by phosphine-initiated cyclization of various enynes bearing a carbonyl group at the ene end in the presence of various aldehydes, in moderate to high yields. The reaction may consist of 1,6-addition of phosphine to the enynes, ring closure, and Wittig reaction between the ylid resulting from cyclization and an aldehyde. Thus, various aldehydes were able to be used in the reaction. The reaction was influenced greatly by the substituents at the acetylene position (R1) and the α-position of the carbonyl group (R3).

Transition metal-catalyzed oxidations. 12 : α-Chlorination of silylenol ethers with tert-butyl hydroperoxide and TiCl2(OiPr)2

Enolsilyl ethers (4, 6, 8, 10, 12, 14) are chlorinated to the α-monochloro ketones (5, 7, 9, 11, 13, 15) with tert-butyl hydroperoxide in the presence of dichlorotitanium diisopropoxide in 69 - 92% yield. WILEY-VCH Verlag GmbH, 1999.

Magnesium bis(diisopropylamide), a useful reagent for regio- and stereoselective synthesis of kinetic silyl enol ethers

Less highly substituted silyl enol ethers are regiospecifically prepared in high yield, around room temperature under kinetic conditions, from unsymmetrical cyclic ketones and magnesium bis(diisopropylamide) [(DA)2Mg] in THF/heptane. This high regioselectivity is markedly higher than these reported for bromomagnesium diisopropylamide (DAMgBr); it is also similar to this of LDA/DME at -78°C, but (DA)2Mg can be used at room temperature. In addition, a high E-enolization stereoselectivity is observed for benzylic ketones, reverse of this obtained with LDA.

The reduction of α-silyloxy ketones using phenyldimethylsilyllithium

Phenyldimethylsilyllithium reacts with acyloin silyl ethers RCH(OSiMe3)COR 8 to give regiodefined silyl enol ethers RCH=C(OSiMe2Ph)R 9, and hence by hydrolysis ketones RCH2COR 10. The yields can be high but are usually moderate. The mechanism of this reduction is established to involve a Brook rearrangement (Scheme 6) rather than a Peterson elimination (Scheme 1). Although the mechanism appears to be the same in each case, the stereochemistries of the silyl enol ethers 9 are opposite in sense in the aromatic series (R = Ph, Scheme 7) and the aliphatic series (R = cyclohexyl, Scheme 8), with the major aromatic silyl enol ether being the thermodynamically less stable isomer E-PhCH=C(OSiMe2Ph)Ph E-9aa, and the major aliphatic silyl enol ether being the thermodynamically more stable isomer Z-c-C6H11CH= C(OSiMe2Ph)-c-C6H11 Z-9ba. This is a consequence of anomalous anti-Felkin attack in the aromatic series. The reaction with the silyl ether ButCH(OSiMe3)COPh 13b is normal in giving Z-ButCH= C(OSiMe2Ph)Ph Z-38 (Scheme 11), but reduction of the silyl ether 8a with lithium aluminium hydride is also anti-Felkin giving with high selectivity the meso diol PhCH(OH)CH(OH)Ph 39. The reaction between Phenyldimethylsilyllithium and the acyloin silyl ether 8d (R = But) does not give the ketone ButCH2COBut, but gives instead the anti-Felkin meso diol ButCHOHCHOHBut 40 also with high selectivity (Scheme 12). Silyllithium and some related reagents react with trifluoromethyl ketones 46 and 48 to give α,α-difluoro silyl enol ethers 47 and 49 (Scheme 14).

First synthesis of Se-(β-Oxoalkyl) selenothiophosphates

General synthesis of a new class of Se-(β-oxoalkyl) selenothiophosphates based on selenothiophosphorylation of silyl enol ethers with thioxophosphoraneselenyl bromide is described.

Regio- and stereoselective synthesis of silyl enol ethers using a new base electrogenerated from hexamethyldisilazane

The hexamethyldisilazane magnesium salt, a new base readily electrogenerated in an undivided cell fitted with a sacrificial magnesium anode, using a normally equilibrating medium (DME/15% vol HMPA mixture), exhibited a surprising regioselectivity leading to the less highly substituted silyl enol ethers from unsymmetrical ketones. This regioselectivity was not temperature dependent, but was strongly dependent on the nature and proportions of the solvent/cosolvent mixture. Moreover, the reaction was different in pure NMP, and exclusively afforded, from 2-pentanone, the new silylated aldol (56% yield) which resulted from the condensation of the less highly substituted enolate with the ketone.

Stereoselective electrochemical synthesis of silyl enol ethers using a sacrificial magnesium anode

The 2-pyrrolidone magnesium salt electrogenerated in an undivided cell fitted with a sacrificial magnesium anode allowed the stereoselective synthesis of Z-silyl enol ethers upon deprotonation of enolizable ketones in the presence of a complexing agent. Keywords: Silyl enol ethers; Stereoselective synthesis; Electrogenerated bases; Sacrificial magnesium anode

Chemistry of oxaziridines. 14. Asymmetric oxidation of ketone enolates using enantiomerically pure (camphorylsulfonyl)oxaziridine

The reagent-controlled asymmetric oxidation of tri- and tetrasubstituted ketone enolate anions 4 and 8 by enantiomerically pure (camphorylsulfonyl)oxaziridine 2 has been investigated. The stereoselectivities for oxidation of trisubstituted enolates 4a-d are good to excellent, 60-95% ee, while those for tetrasubstituted enolates 4e and 8 are lower; i.e., 21-30% ee. Isolated chemical yields for both types of enolate anions are good to excellent. The sodium enolate anions of 4a-d, which could be oxidized at -78°C, gave both higher yields and stereoselectivities than the corresponding lithium or zinc enolates, which required warming to higher temperatures for complete oxidation. The presence of HMPA generally had a deleterious effect on the stereoinduction. However, for oxidation of (E)- and (Z)-4d the highest ee's were observed in the presence of this additive. Investigation of the stereoselective trends reveals that the enolate substitution pattern and the enolate solution structure are the most important stereocontrol elements. The role that the enolate geometry has in the stereoinduction is less clear although Z enolates seem to exhibit higher stereoselectivities than the E enolates. The results obtained in this study have been formulated into a mechanistic rational involving an SN2-type substitution of the enolate anion on oxaziridine 2 via an "open" transition state.