Hydroxyethyl groups, from aminoethyl

In close analogy to the 2-hydroxyethyl radical 21 (R = H) the 2-aminoethyl radical 24 faces a substantial barrier for the (most likely stepwise) 1,2-migration process. A transition state for the concerted migration pathway such as 25 could up to now not be located. What differentiates the amino 1,2-migration from the corresponding hydroxy group migration is that the former appears to be less affected... 

Figure 7-14A). The base peak at m/z 305 might arise from the neutral loss of a 2-vinylamino-ethanol. The product ions formed by the neutral loss of 73 (2-methyleneamino-ethanol) and 44 (Ethenol) Da from the precursor ion of m/z 392 were also consistent with the proposed structure (Figure 7-15A). The production spectra of impurities D and E were similar in two ways. Both have a base peak at m/z 88 which was produced when an A-(2-hydroxyethyl) aminoethyl group was cleaved from the molecule. Both produce a less intense product ion that was 61 Da less than the precursor ion (Figure 7-15 m/z 278 in D, and m/z 263 in E). This 61-Da loss was found to be the loss of a 2-aminoethanol neutral. Further studies suggested that impurities D and E are photo-decomposition products of DuP 941[87]. Based on the LC/MS/MS data,... 

In the 1980s, the successful synthesis of elastomeric polyamides 120 of high molecular weight (d/n =10,000-18,000) was reported from the polycondensation of l,l -bis(/ -aminoethyl)ferrocene with diacid chlorides (Scheme 13). Also, polyureas 121 were prepared from the same ferrocene monomer and diisocyanates, and polyesters and polyurethanes were prepared from l,l -bis(/ -hydroxyethyl)ferrocene. However, the latter materials had much lower molecular weights and were characterized only by scanning electron microscopy. X-ray, and IR analyses. The introduction of ferrocenes in which the functional groups are separated from the cyclopentadienyl ring by at least two methylene units was crucial in order to reduce steric effects and to avoid the instability found previously in polymers of a-functionalized ferrocene due to the a-ferrocenyl carbonium ion stability. 

---