Study of palladium catalyst deactivation in synthesis of 4,10-diformyl-2,6,8,12-tetraacetyl-2,4,6,8,10,12-hexaazaisowurtzitane

Koskin, Anton P.; Simakova, Irina L.; Parmon, Valentin N.

doi:10.1007/s11144-007-5203-4

Cited by 18 publications

(7 citation statements)

References 4 publications

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“…, 1 → 2 and 1 → 2 → 3 . Similarly, it can be found that the used catalysts were easily deactivated for hydrogenolysis of HBIW as reported. − Surprisingly, the Pd/TiO 2 -2 can be recycled for only TADBIW hydrodebenzylation ( 2 → 3 ).…”

Section: Resultssupporting

confidence: 68%

“…The cleavage of the C–N bond via hydrogenolysis is one of the most frequently used deprotecting classifications for amino functionalities with benzyl groups in the fields of fine chemistry as well as pharmaceuticals and the military. − The hydrogenolysis reactions are commonly based on heterogeneous Pd-based catalysts. However, some significant problems for practical application often appear, such as low yields for some special debenzylation reactions, , a high precious metal loading and usage amount, and poor stability. − Varieties of Pd particle catalysts have to be explored in order to improve the cost efficiency of debenzylation processes, such as Pd particles supported on different carbons, , Pd/Al 2 O 3 , Pd/In 2 O 3 , Pd/SiO 2 , − Pd/DOWEX, and others. ,− Recently, Ananikov et al reported that Vulcan XC-72 carbon carried 1 wt % Pd particles disclosed with a high turnover number (TON) up to 5000 with a low usage amount of only 0.02–0.3 mol % of Pd for the transfer hydrodebenzylation system with HCO 2 H as the reductant. From the viewpoint of practical applications, development of more cost-effective Pd catalysts is still an attractive topic to debenzylation.…”

Section: Introductionmentioning

confidence: 99%

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Ultrasmall Pd Nanoparticles Supported on TiO₂ for Catalytic Debenzylation via Hydrogenative C–N Bond Cleavage

Zhao

Liu

Wang

et al. 2020

ACS Appl. Nano Mater.

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Heterogeneous Pd has been developed as a well-known catalyst for debenzylation reactions via hydrogenative C−N bond cleavage. However, the extensive applications are still limited owing to a high loading and usage amount of the noble metal. Herein, well-dispersed Pd nanocatalysts over TiO 2 were explored with a deposition−precipitation method and characterized by FESEM, physical adsorption, XRD, TEM, and XPS. It was proposed that the ultrasmall and electronrich Pd nanoparticles can be enhanced over TiO 2 rather than C, Al 2 O 3 , or SiO 2 . As representatives, the debenzylations of hexabenzylhexaazaisowurtzitane (HBIW) and tetraacetyldibenzylhexaazaisowurtzitane (TADBIW), which are key steps for the synthesis of CL-20 with the highest energy and density, were selected to evaluate the catalytic performances. It was found that Pd/TiO 2 exhibited considerably low usage with high yields in the debenzylation processes of not only HBIW (1 wt ‰) but also TADBIW (4 wt ‰). Meanwhile, the superior catalytic activities can be maintained in the different reaction scales and can be repeated for TADBIW hydrodebenzylation. Hence, Pd nanoparticles supported on TiO 2 can be considered to be suitable catalysts for highly efficient catalytic synthesis for hydrogenative C−N bond cleavage.

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Section: Resultssupporting

confidence: 68%

Section: Introductionmentioning

confidence: 99%

Ultrasmall Pd Nanoparticles Supported on TiO₂ for Catalytic Debenzylation via Hydrogenative C–N Bond Cleavage

Zhao

Liu

Wang

et al. 2020

ACS Appl. Nano Mater.

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“…Стадия восстановительного дебензилирования вносит наиболее значимый вклад в стоимость ГАВ. Катализатор подвергается отравлению продуктами дебензилирования и требует частой замены [15].…”

Section: рис 1 синтез гав через трансформацию гбunclassified

synthesis of oxaazaisowurtzitane derivatives by condensation of p-toluenesulfonamide with glyoxal

Паромов,

Кубасова,

Сысолятин

2023

Южно-Сибирский Научный Вестник

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Синтез легконитруемых производных 2,4,6,8,10,12-гексаазатетрацикло[5.5.0.03,11.05,9]додекана (2,4,6,8,10,12-гексаазаизовюрцитана) – прекурсоры перспективного высокоэнергетического соединения 2,4,6,8,10,12-гексанитро-2,4,6,8,10,12-гексаазаизовюрцитана (CL-20, HNIW, ГАВ), методом прямой конденсации является сложной задачей. С момента открытия данных соединений в середине 90-х годов и до настоящего времени не останавливаются попытки разработать доступный способ синтеза данных веществ. На данный момент синтез ГАВ все еще остается слишком дорогим. Выбор исходных производных аммиака для получения производных 2,4,6,8,10,12-гексаазаизовюрцитана весьма ограничен. Важным шагом в разработке альтернативного двустадийного способа синтеза легконитруемых производных 2,4,6,8,10,12-гексаазаизовюрцитана, который радикально может снизить стоимость ГАВ, является детальное исследование процесса формирования каркаса 2,4,6,8,10,12-гексаазаизовюрцитана. В данной работе представлены данные исследования реакции конденсации п-толуолсульфонамида с глиоксалем в мольном соотношении 2 : 1 в среде водной H2SO4 с целью исследования процессов образования и синтеза новых производных аза- и оксаазаизовюрцитанов. В работе получено три новых оксаазаизовюрцитана различной структуры включающие одну и две азагруппы. Показано влияние кислотности реакционной среды на процесс. В частности, отмечена низкая устойчивость некоторых соединений. А также разработан способ разделения двух полученных изомерных оксаазаизовюрцитанов: 2,6,8,12-тетраокса-4,10-диаизовюрцитана и 6,10,2,4,8,12-тетраокса-6,10-диазаизовюртцитана, с помощью препаративной хроматографии. The synthesis of easily nitratable derivatives of 2,4,6,8,10,12-hexaazatetracyclo[5.5.0.03,11.05,9]dodecane (2,4,6,8,10,12-hexazaisowurtzitane), the precursors of the promising high-energy compound 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12- hexazaisowurtzitane (CL-20, HNIW), via the direct condensation is challenging. Since the discovery of these compounds in the mid-1990s and to the present, there has been no stop in the attempts to develop a facile synthetic method for these compounds. At present, the synthesis of HNIW still remains to be very espensive. The selection of starting ammonia derivatives for the synthesis of 2,4,6,8,10,12-hexazaisowurtzitane derivatives is rather limited. The important step in the development of an alternative two-stage synthetic method for easily nitratable 2,4,6,8,10,12-hexazaisowurtzitane derivatives, which can cardinally reduce the cost of HNIW, is a detailed study on the formation process of the 2,4,6,8,10,12-hexazaisowurtzitane cage. This paper reports the study results on the condensation reaction between p-toluenesulfonamide and glyoxal in a molar ratio of 2 : 1 in aqueous H2SO4 in order to examine the formation processes of aza- and oxaazaisowurtzitanes. Three new oxaazaisowurtzitanes differing in structure were synthesized herein that incorporate one or two aza groups. In particular, some compounds were noted to be low-stability. In addition, a method was developed for the separation of the two resultant isomeric oxaazaisowurtzitanes, 2,6,8,12-tetraoxa-4,10-diazaisowurtzitane and 6,10,2,4,8,12-tetraoxa-6,10-diazaisowurtzitane, by preparative chromatography.

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“…TADF) have been reported. 619,620 The studies concerned the effects of the preparation procedure of heterogeneous catalysts, components of the reaction mixture and process conditions on the catalyst stability against deactivation in the catalytic debenzylation. Using modern methods of analysis, the authors established the optimal degree of dispersion of Pd on the support surface for debenzylation.…”

Section: Scheme 149mentioning

confidence: 99%

Development of new methods in modern selective organic synthesis: preparation of functionalized molecules with atomic precision

Ananikov¹,

Khemchyan²,

Іvanova³

et al. 2014

Russ. Chem. Rev.

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Study of palladium catalyst deactivation in synthesis of 4,10-diformyl-2,6,8,12-tetraacetyl-2,4,6,8,10,12-hexaazaisowurtzitane

Cited by 18 publications

References 4 publications

Ultrasmall Pd Nanoparticles Supported on TiO₂ for Catalytic Debenzylation via Hydrogenative C–N Bond Cleavage

Ultrasmall Pd Nanoparticles Supported on TiO₂ for Catalytic Debenzylation via Hydrogenative C–N Bond Cleavage

synthesis of oxaazaisowurtzitane derivatives by condensation of p-toluenesulfonamide with glyoxal

Development of new methods in modern selective organic synthesis: preparation of functionalized molecules with atomic precision

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Study of palladium catalyst deactivation in synthesis of 4,10-diformyl-2,6,8,12-tetraacetyl-2,4,6,8,10,12-hexaazaisowurtzitane

Cited by 18 publications

References 4 publications

Ultrasmall Pd Nanoparticles Supported on TiO2 for Catalytic Debenzylation via Hydrogenative C–N Bond Cleavage

Ultrasmall Pd Nanoparticles Supported on TiO2 for Catalytic Debenzylation via Hydrogenative C–N Bond Cleavage

synthesis of oxaazaisowurtzitane derivatives by condensation of p-toluenesulfonamide with glyoxal

Development of new methods in modern selective organic synthesis: preparation of functionalized molecules with atomic precision

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Ultrasmall Pd Nanoparticles Supported on TiO₂ for Catalytic Debenzylation via Hydrogenative C–N Bond Cleavage

Ultrasmall Pd Nanoparticles Supported on TiO₂ for Catalytic Debenzylation via Hydrogenative C–N Bond Cleavage