On September 30, 1988, Urtane, I.; Zelcans, G.; Lukevics, E.; Mazeika, I.; Gaukhman, A. P. published an article.Electric Literature of 2160-93-2 The title of the article was Synthesis and mass spectra of spirocyclic silicon ethers of diethanolamines. And the article contained the following:
Heating Si(OMe)4 or Si(OEt)4 with glycols Z(OH)2 [Z = CH2CH2, (CH2)3, CMe2CMe2, C(CF3)2C(CF3)2, CMe2CH2CMe2; CMe2CH2CMeR, R = nonyl] and diethanolamines (HOCHR1CH2)2NR2 (R1 = H, Me; R2 = H, Me, CMe3) gave 29-100% of 13 asym. spirocyclic ethers I (same Z, R1, R2). Heating Si(OMe)4 with (HOCHMeCH2)2NMe or with (Me3SiOCH2CH2)2NPh gave 33-36% sym. spirocyclic ethers I [Z = R2N(CH2CHR1O)2; R1 = R2 = Me; R1 = H, R2 = Ph], resp. Mass spectral fragmentation patterns for I indicate a pronounced transannular N→Si bond in the mixed spirocycles and a much weaker one in the sym. spirocycles. The experimental process involved the reaction of 2,2′-(tert-Butylazanediyl)diethanol(cas: 2160-93-2).Electric Literature of 2160-93-2
The Article related to spirocyclic silicon ether preparation mass spectrum, diethanolamine cyclocondensation alkoxysilane glycol, transannular nitrogen silicon bond spirocycle, Organometallic and Organometalloidal Compounds: Silicon Compounds and other aspects.Electric Literature of 2160-93-2
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