01265nas a2200253 4500008004100000022001400041245010900055210006900164260000900233300001500242490000700257520044600264653001200710653002300722653001800745653002400763100001700787700001900804700001800823700002100841700001700862700001900879856011300898 2022 eng d a1867-388000aWell-defined calcium compound catalyzes trimerization of arylisocyanates into 1,3,5-triarylisocyanurates0 aWelldefined calcium compound catalyzes trimerization of arylisoc cJUN  ae2021017880 v143 a

We report the synthesis of a calcium complex (2) bearing a tetradentate monoanionic ligand with a diaminoethane core and phenolate and pyridine peripheral donors. Single crystal X-ray studies on 2 revealed that LiI was also co-crystallized, leading to a four-membered ring with four different elements. 2 was found to be an efficient catalyst for the cyclotrimerization of a variety of aromatic isocyanates under mild conditions.

10acalcium10aCyclotrimerization10aIsocyanurates10aTetradentate ligand1 aKumar, Rohit1 aSharma, Vishal1 aJain, Shailja1 aSharma, Himanshu1 aVanka, Kumar1 aSen, Sakya, S. uhttps://library.ncl.res.in/content/well-defined-calcium-compound-catalyzes-trimerization-arylisocyanates-13501252nas a2200241 4500008004100000022001400041245008400055210006900139260000800208490000700216520048300223653002300706653003000729653001400759653001400773653001600787100002300803700002000826700002700846700001900873700001900892856009900911 2025 eng d a1434-194800aC=C insertion over N=C=O of allyl isocyanate into the Ge-Si bond of a germylene0 aCC insertion over NCO of allyl isocyanate into the GeSi bond of  cSEP0 v283 a

Two isocyanates are reacted with the germylene, PhC(NtBu)(2)Ge-Si(SiMe3)(3) (1). Phenyl isocyanate undergoes catalytic cyclotrimerization with 1 leading to 1,3,5-triphenyl isocyanurate (2), while allyl isocyanate undergoes both cyclotrimerization and the C=C bond insertion between the Ge-Si bond. The constitution of 3 is determined by single-crystal X-ray studies. The contrasting reactivity pattern is explained by comprehensive density functional theory studies.

10aCyclotrimerization10aDensity functional theory10aGermylene10aInsertion10aisocyanates1 aAjithkumar, V., S.1 aKhilari, Nripen1 aGhanwat, Pratiksha, B.1 aKoley, Debasis1 aSen, Sakya, S. uhttps://library.ncl.res.in/content/cc-insertion-over-nco-allyl-isocyanate-ge-si-bond-germylene