7062-97-7

Upstream product

• 89534-58-7 1-acetoxy-1,2-dimethoxy-ethane 
• 24332-20-5 methoxyacetaldehyde dimethylacetal 
• 7062-96-6 (Z)-1,2-Dimethoxyethylen 

Downstream Products

• 128792-66-5 1-(4-methylphenylsulfonyl)-1-trans,2-trans,3-cis-trimethoxycyclopropane 
• 128898-71-5 1-(4-methylphenylsulfonyl)-1,2,3alltrans-trimethoxycyclopropane 
• 82656-30-2 5-Acetyl-3,4-dihydro-r-2,t-3-dimethoxy-6-methyl-t-4-phenyl-2H-pyran 
• 82656-30-2 5-Acetyl-3,4-dihydro-r-2,t-3-dimethoxy-6-methyl-c-4-phenyl-2H-pyran 

Relevant academic research and scientific papers

Photoaddition of Biacetyl and Alkenes. Reaction Stereochemistry, Multiplicity, and Photokinetics

Quantum yields are reported for the photoaddition of biacetyl with the alkenes indene, 2,3-dimethyl-2-butene, furan, and 1,2-dimethoxyethene in benzene solution.The dependence of quantum efficiencies on alkene concentration is consistent with a photoaddition mechanism involving biacetyl triplets.The quenching of fluid solution biacetyl phosphorescence has been observed, and quenching constants correlate with the electron-donor ability (ionization potentials) of the alkenes.Photoaddition of biacetyl and 1,2-dimethoxyethene is nonstereospecific, and oxetane formation is accompanied by the isomerization of the starting alkene.Stereochemical results are used to estimate relative rates of cleavage, closure, and stereorandomizing bond rotation in biradicals, proposed intermediates in photoaddition.Exciplexes of triplet biacetyl and alkenes are proposed as primary photochemical intermediates (precursors to biradicals) on the basis of stereochemical, emission quenching, and other data.

Gas-phase synthesis and reactivity of a gold carbene complex

Electrospray ionization tandem mass spectrometry of a phosphonium ylid complex of gold produces an ion whose mass and gas-phase chemical reactivity indicate that it is a gold benzylidene complex. The complex, with a supporting NHC ligand, corresponds to a

17O, 13C and 1H NMR spectra of 1,2-dialkoxyethenes

The 17O, 13C and 1H NMR spectra of a number of 1,2-dialkoxyethenes R1OCH=CHOR2 were recorded. The O atoms, in particular those of the E forms, are strongly shielded relative to the 17O nuclei of the corresponding alkyl vinyl ethers ROCH=CH2. Moreover, in compounds of the type ROCH=CHOMe, the difference δ(17O)Z - δ(17O)E of the MeO group decreases and that of the RO group increases with increasing bulkiness of R. These trends probably arise from changes, with the size of the alkyl group R, in the stereochemistry of the RO group of the E-isomer about the O - C(sp2) bond, whereas the stereochemistry of the Z-form seems to be independent of the size of R. Additional information on the stereochemistry of the title compounds is provided by their 13C and 1H NMR spectra.

Enolate Additions to a Chiral 3-Hydroxypropionate 2,3-Dication Equivalent. Enantioselective Synthesis of β,δ-Dihydroxy Esters

The use of optically active dicarbonyl cyclopentadienyliron(vinyl ether) BF4 salts, 3 and 4, as enantioselective 3-hydroxypropionate 2,3-dication equivalents is outlined.Complexes 3 and 4 are readily available by exchange etherification of 2, and these have been transformed to enantiomeric dicarbonyl (η-cyclopentadienyliron)(η2-1-methoxypropene) BF4 5 and ent-5.Complex 5 has been converted to the corresponding p-methoxybenzyloxy vinyl ether complex 7 by exchange etherification.Condensation of this salt with a number of terminal and nonterminal enolates yields adducts, which are then transformed by redox-promoted alkoxycarbonylation, followed by alcohol deprotection, to optically active 2-methyl-3-hydroxy-5-keto esters. 1,3-Reduction of these ketols can be effected to give either syn- or anti-1,3-diols and thence their related pentanolides.

Stereochemistry of Additions of m-Quinomethane to Olefins and Acyclic Dienes

The m-quinomethane biradical has a triplet ground state, as judged by the temperature dependence of the intensity of its EPR signal.When generated by pyrolysis or photolysis of 6-methylenebicyclohex-3-en-2-one, it adds to olefinic trapping agents to give phenolic indans.Retention of configuration dominates by a factor of 13-17 with cis-1,2-dimethoxyethene and by a factor of >100 with trans-1,2-dimethoxyethene.With the 2,4-hexadienes, which undergo addition to give phenolic 1-propenylindans, retention again is the favored pathway, but the preference is lower (up to 6-fold).The propenyl stereochemistry in the product is completely retained.A comparison with known results of cycloadditions of trimethylenemethane (singlet) biradical and of m-quinodimethane shows that m-quinomethane additions are intermediate between the other two in cis stereospecifity.A mechanistic rationale for this ordering is discussed.

Photochemical reactions of charge-transfer complexes. IV. The orientation effects of charge-transfer complexes: theory and experiment

In paper number III of this series (2) ab initio and PCILO molecular orbital calculations for the four ?-?* charge-transfer (ct) complexes formed between maleonitrile (MN) and fumaronitrile (FN), and cis (CS) and trans-1,2-dimethoxyethylene (TR) were reported.This paper reports the ct transition absorption characteristics and association constans of these complexes as a function of temperature.From this data the heats of formation of the complexes are determined and these experimental results are then compared with the theoretical values; good agreement is obtained.The order of complex stability ( (kcal mol)) measured in chloroform solution is: MN-TR(0.55) FN-TR(0.65) MN-CS(0.78) FN-CS(1.25) we reach the conclusion that for these complexes orientation effects of the substituents are quite small in magnitude and that the dominant factor influencing complex stability follows the redox potential difference.The structures of the complexes are discussed in view of these results.