The value of 2 J P–CO as a diagnostic parameter for the structure and thermal reactivity of carbonyl-stabilised phosphonium ylides
作者:R. Alan Aitken、Youcef Boubalouta、Da Chang、Lee P. Cleghorn、Ian P. Gray、Nazira Karodia、Euan J. Reid、Alexandra M.Z. Slawin
DOI:10.1016/j.tet.2017.09.016
日期:2017.11
A survey of 20 carbonyl-stabilised phosphonium ylides with recently reported X-ray structures shows a strong correlation between the CP to CO torsion angle and the value of 2JP–CO, with high values being associated with an anti configuration and low with syn. Seven new X-ray structural determinations are reported, several for types of ylide not crystallographically characterised before, and these also
A process including forming a siloxane oligomer from a mixture including at least one alkoxysilane, at least one phase transfer catalyst, and water, and adding at least one latent curing catalyst to the siloxane oligomer to form a coating composition is described. Also described is a process for producing a rapidly cured abrasion resistant coating, including providing a coating composition including a siloxane oligomer and a thermal latent curing catalyst, applying the coating composition to an article, and curing the coating composition for less than about 10 minutes to form a coating that has a Bayer ratio of abrasion resistance of at least about 2.0. A coating composition including at least one siloxane oligomer, at least one phase transfer catalyst, and at least one latent curing catalyst is also described.
US7329715B2
申请人:——
公开号:US7329715B2
公开(公告)日:2008-02-12
Ohmori, Hidenobu; Maeda, Hatsuo; Tamaoka, Mie, Chemical and pharmaceutical bulletin, 1988, vol. 36, # 2, p. 613 - 620
Reactivity of 2-Halo-2H-azirines. Part II. Thermal Ring Expansion Reactions: Synthesis of 4-Haloisoxazoles
作者:Teresa M. V. D. Pinho e Melo、Cláudia S. J. Lopes、António M. d’A. Rocha Gonsalves、Richard C. Storr
DOI:10.1055/s-2002-23542
日期:——
The thermolysis of haloazidoalkenes and 2-halo-2H-azirines is described. 2-Benzoyl-2-halo-2H-azirine-3-carboxylates (2a and 2b) underwent ringexpansion leading to the synthesis of new 4-haloisoxazoles in high yield. The same isoxazoles were also obtained in high yield directly from haloazidoalkenes (la and 1b). The thermolysis of the β-azido-α,β-unsaturated ketone 1e led to complete conversion to