37902-49-1

Upstream product

• 106-42-3 para-xylene 
• 6832-16-2 methyl diazoacetate 
• 638-02-8 2,5-DIMETHYLTHIOPHENE 
• 762-42-5 dimethyl acetylenedicarboxylate 
• 18063-93-9 dimethyl 1,4-dimethyl-7-oxabicyclo[2.2.1]hepta-2,5-diene-2,3-dicarboxylate 
• 18063-93-9 dimethyl 1,4-dimethyl-7-oxabicyclo[2.2.1]hepta-2,5-diene-2,3-dicarboxylate 
• 78607-42-8 N,N-dibenzylaminopyrrole 
• 592-46-1 hexa-2,4-diene 

Downstream Products

• 43183-80-8 3,6-Bis-(brommethyl)-phthalsaeure-dimethylester 
• 58791-51-8 6-Brommethyl-3-dibrommethylphthalsaeure-dimethylester 
• 944-38-7 3,6-dimethylphthalic acid 

Relevant academic research and scientific papers

?-Facial Diastereoselectivity in Diels-Alder Reactions of 2,5-Dimethylthiophene Oxide

A series of cycloadditions with 2,5-dimethylthiophene oxide (2), generated in situ by peracid oxidation of 2,5-dimethylthiophene (1), are described.In all cases the syn adduct (with respect to the sulfoxide oxygen) is formed exclusively.

Regioselective arene homologation through rhenium-catalyzed deoxygenative aromatization of 7-oxabicyclo[2.2.1]hepta-2,5-dienes

Combined use of oxorhenium catalysts with triphenyl phosphite as an oxygen acceptor allowed efficient deoxygenative aromatization of oxabicyclic dienes. The reaction proceeded under neutral conditions and was compatible with various functional groups. Combining this deoxygenation with regioselective bromination and trapping of the generated aryne with furan resulted in benzannulative π-extension at the periphery of the PAHs. This enabled direct use of unfunctionalized PAHs for extension of π-conjugation. Iteration of the transformations increased the number of fused-benzene rings one at a time, which has the potential to alter the properties of PAHs by fine-tuning the degree of π-conjugation, shape, and edge topology.

Cycloaddition of thiophene S-oxides to allenes, alkynes and to benzyne

Thiophenes have been treated with alkynes in the presence of m-chloroperoxybenzoic acid to give substituted arenes as cycloadducts. Alternatively, thiophene S-oxides have been prepared by oxidation from thiophenes and have been subjected to cycloaddition with alkynes in a subsequent step. The outcome of the reaction is dependent on the steric demand of the thiophene S-oxide. Some thiophene S-oxides can be reacted at temperatures as high as 140°C without decomposition. Thiophenes as deoxygenated products are the main by-products. Reactions of thiophene S-oxides with allenes give in part thiabicyclo[2.2.1]heptene S-oxides of type 12a and 13 along with aromatized products. Thiophene S-oxides also cycloadd to benzyne.

MOLYBDENUM-PROMOTED REACTIONS OF 7-OXABICYCLOHEPTADIENE AND DERIVATIVES

The reactions of 2,3-bis(methoxycarbonyl)-7-oxabicycloheptadiene (1a) and related compounds 1b, 1c, and 2 with molybdenum carbonyl complexes are examined at two different temperatures.In refluxed cyclohexane, reactions of 1a-c with hexacarbonylmolybdenum produce mainly the corresponding derivatives of dimethyl phthalate (3a-c) and 3,4-bis(methoxycarbonyl)furan (4a-c), while the reaction of 2 produces naphthalene and 1-naphthol.At room temperature, reactions of 1a,b with tris(acetonitrile)tricarbonylmolybdenum yield the dimer ketones 5a,b in addition to 3a,b and 4a,b, while the reaction of 2 produces naphthalene as the only prod uct.The mechanism for the generation 3, 4, and 5 is rationalized as going through complex intermediate with structure of a molybdenum chelated by 1.

Arene synthesis by extrusion reaction X. Synthesis of arenes by deoxygenation of endoxides with cyclopentadienyltitanium trichloride/lithium aluminum hydride and dicyclopentadienyltitanium dichloride/lithium aluminum hydride

The two homogeneous systems, cyclopentadienyltitanium trichloride/lithium aluminum hydride and dicyclopentadienyltitanium dichloride/lithium aluminum hydride have been utilized to deoxygenate 1,4-endoxides in tetrahydrofuran.The results show that they can provide corresponding arenes in fair yields.

AROMATIC RING SYNTHESIS BY N-AMINOPYRROLE DIELS-ALDER REACTION. CHARACTERIZATION OF THE HETEROATOM FRAGMENT

Aminonitrenes are produced on reaction of N-aminopyrroles with dimethyl acetylenedicarboxylate; a new reaction of dialkyl aminonitrenes is described.