86031-12-1Relevant articles and documents
Photo-on-Demand Base-Catalyzed Phosgenation Reactions with Chloroform: Synthesis of Arylcarbonate and Halocarbonate Esters
Dai, Namin,Eda, Kazuo,Harada, Hidefumi,Hashimoto, Yuka,Hosokawa, Sasuga,Kakiuchi, Toshifumi,Liang, Fengying,Okazoe, Takashi,Suzuki, Yuto,Tana, Gegen,Tsuda, Akihiko
, p. 9811 - 9819 (2021/07/20)
Carbonate esters are utilized as solvents and reagents for C1 building blocks in organic synthesis. This study reports a novel photo-on-demand in situ synthesis of carbonate esters with CHCl3 solutions containing a mixture of an aromatic or haloalkyl alcohol having relatively high acidity, and an organic base. We found that the acid-base interaction of the alcohol and base in the CHCl3 solution plays a key role in enabling the photochemical reaction. This reaction allows practical syntheses of diphenyl carbonate derivatives, haloalkyl carbonates, and polycarbonates, which are important chemicals and materials in industry.
Diaryloxycarbenes from oxadiazolines
Lu,Reid,Warkentin
, p. 319 - 327 (2007/10/03)
Symmetric and unsymmetric 2,2-diaryloxy-5,5-dimethyl-Δ3-1,3,4-oxadiazolines were synthesized by oxidative cyclization of aryloxycarbonyl hydrazones of acetone with lead tetraacetate and subsequent treatment of the product mixture with a phenol in acidic solution. Thermolysis of the oxadiazolines in benzene solution at 110°C afforded carbonyl ylide intermediates that cyclize, in part, to the corresponding 2,2-diaryloxyoxirane intermediates. The oxiranes, which were not observed, are required to account for the 1,1-diaryloxy-2-methylpropenes (ketene acetals) that were isolated. Most of the carbonyl ylides fragment to acetone and diaryloxycarbenes. The latter form dimers (tetraaryloxyethenes) or they can be trapped with phenols to form orthoformates. Diphenoxycarbene was also trapped with dimethyl acetylenedicarboxylate (DMAD). The method appears to be the first for generating the parent diphenoxycarbene under relatively mild conditions in solution, and the only one to date for generating unsymmetrically substituted diaryloxycarbenes. Minor competing fragmentations of the oxadiazolines to 2-diazopropane and the appropriate diaryl carbonates, were also observed.