Application In Synthesis of 6-Bromo-2,3-dihydrobenzo[b][1,4]dioxine. The mechanism of aromatic electrophilic substitution of aromatic heterocycles is consistent with that of benzene. Compound: 6-Bromo-2,3-dihydrobenzo[b][1,4]dioxine, is researched, Molecular C8H7BrO2, CAS is 52287-51-1, about Ex Situ Generation of Stoichiometric and Substoichiometric 12CO and 13CO and Its Efficient Incorporation in Palladium Catalyzed Aminocarbonylations. Author is Hermange, Philippe; Lindhardt, Anders T.; Taaning, Rolf H.; Bjerglund, Klaus; Lupp, Daniel; Skrydstrup, Troels.
A new technique for the ex situ generation of carbon monoxide (CO) and its efficient incorporation in palladium catalyzed carbonylation reactions was achieved using a simple sealed two-chamber system. The ex situ generation of CO was achieved by a palladium catalyzed decarbonylation of tertiary acid chlorides using a catalyst originating from Pd(dba)2 and P(tBu)3. Preliminary studies using pivaloyl chloride as the CO-precursor provided an alternative approach for the aminocarbonylation of 2-pyridyl tosylate derivatives using only 1.5 equiv of CO. Further design of the acid chloride CO-precursor led to the development of a new solid, stable, and easy to handle source of CO for chem. transformations. The synthesis of this CO-precursor also provided an entry point for the late installment of an isotopically carbon-labeled acid chloride for the subsequent release of gaseous [13C]CO. In combination with studies aimed toward application of CO as the limiting reagent, this method provided highly efficient palladium catalyzed aminocarbonylations with CO-incorporations up to 96%. The ex situ generated CO and the two-chamber system were tested in the synthesis of several compounds of pharmaceutical interest and all of them were labeled as their [13C]carbonyl counterparts in good to excellent yields based on limiting CO. Finally, palladium catalyzed decarbonylation at room temperature also allowed for a successful double carbonylation. This new protocol provides a facile and clean source of gaseous CO, which is safely handled and stored. Furthermore, since the CO is generated ex situ, excellent functional group tolerance is secured in the carbonylation chamber. Finally, CO is only generated and released in minute amounts, hence, eliminating the need for specialized equipment such as CO-detectors and equipment for running high pressure reactions.
There is still a lot of research devoted to this compound(SMILES：BrC1=CC=C2OCCOC2=C1)Application In Synthesis of 6-Bromo-2,3-dihydrobenzo[b][1,4]dioxine, and with the development of science, more effects of this compound(52287-51-1) can be discovered.
Reference:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics