Infrared spectroscopy acetyl chloride

The hydroxyl equivalent weight of epoxy resins can be determined by several methods. The most common is esterification with acids, reaction with acetyl chloride, and reaction with lithium aluminum hydride. Infrared spectroscopy may also be used. 

Burton and Praill were the first to prqjare this ecies both by the interaction of perchloric acid with acetic anhydride and the metathetic reaction of sflver perchlorate with acetyl chloride , in a comprehensive study of acylation reactions. They did not attempt a characterisation of the compound and assumed that in acid solutions it existed in a fully ionised form. A few years later, Jander and Surawski followed the formation of acetyl perchlorate in acetic anhydride by measuring the electrical conductivity changes which took place when acetyl bromide was added to silver perchlorate or vice versa. In both titrations an inflection point was observed for a mixture of equimolar quantities of the two reactants indicating the formation of acetyl perchlorate. Moreover, it was clearly drown that this compound was at least partly ionised since its conductivity was higher than that of acetyl bromide. Avedikian and Commeyras characterised acetyl perchlorate by infrared and Raman spectroscopy both in acetic anhydride and carbon tetrachloride. They concluded that some ionisation was present but could not assess its extent. Molecular acetyl perchlorate was also detected. As far as we are aware, no other study of the structure and extent of dissociation of acetyl perchlorate in solution has been conducted. 

D.E.H. Jones and J.L. Wood (ref. 7) used infrared spectroscopy to study the chloride complexes of acidic A1C13. The study of the complexation of acetyl chloride by the various metal halides (Table 1) was performed by measuring the variation of the vibration intensity (CO) at 1808 cm. ... 

Resin Bound CyEIC Piscopio, at Amgen, reported a synthesis of odorless resin-bound CIC Izh based on Armstrong s CIC [108]. It can be prepared from 4-(4-hydroxyphenyl)-cyclohexanone using Merrifield as a base resin. Loading in the 0.7-0.8 mmol/g range was achieved and reactions can be monitored by on-bead Fourier transform infrared spectroscopy. Hulme and coworkers have employed the resin-bound CIC Izh in the so-called UDC (Ugi/De-Boc/Cyclization) strategy to synthesize bicyclic y-lactam 304 [109]. The U-4CR of resin-bound CIC Izi, y-keto acid lOza and amine 6zg affords resin-bound y-lactam 304. Acetyl chloride... 

---