A comprehensive picture on the mechanism of the epoxy-carboxylic acid curing reactions is presented using the density functional theory B3LYP/6-31G(d,p) and simplified physical molecular models to examine all possible reaction pathways. Carboxylic acid can act as its own promoter by using the OH group of an additional acid molecule to stabilize the transition states, and thus lower the rate-limiting barriers by 45 kJ/mol. For comparison, in the uncatalyzed reaction, an epoxy ring is opened by a phenol with an apparent barrier of about 107 kJ/mol. In catalyzed reaction, catalysts facilitate the epoxy ring opening prior to curing that lowers the apparent barriers by 35 kJ/mol. However, this can be competed in highly basic catalysts such as amine-based catalysts, where catalysts can enhance the nucleophilicity of the acid by forming hydrogen-bonded complex with it. Our theoretical results predict the activation energy in the range of 71 to 94 kJ/mol, which agrees well with the reported experimental range for catalyzed reactions. © 2017 Wiley Periodicals, Inc.

The aim of this study was to determine supply practices of Victorian community pharmacies in relation to the emergency contraceptive pill (ECP), following release of an updated guideline by the Pharmaceutical Society of Australia. Telephone call scripts were developed for three scenarios in which the ECP was requested: outside the licensed 72-h time frame (Scenario 1); by a woman under 16 years (Scenario 2); and for future use (Scenario 3). From 1222 pharmacies, 515 were randomly selected and allocated into three groups: 177 to Scenario 1 and 169 to each of Scenarios 2 and 3. Pharmacists' responses were categorised as 'yes', 'no' or 'ambiguous' and descriptive statistics were calculated. The results are as follows. Scenario 1: over half (55.4%; 92/166) declined supply and most referred to the doctor, citing the time frame or the ECP as no longer being effective reasons. Decreased effectiveness was readily discussed among those willing to supply. Scenario 2: more than half (53.9%, 89/165) agreed to supply, assessing the request against eligibility criteria outlined in the guideline; however, 5.6% (5/89) were only willing if the woman obtained a doctor's prescription or recommendation. Scenario 3: less than half (40.5%; 66/163) declined supply, mainly due to no therapeutic need. Only four respondents willing to give the ECP knew that supply was bona fide. In conclusion, pharmacists' practices are variable and not always in line with the recommendations of the Pharmaceutical Society of Australia guideline. Pharmacists' awareness of the guideline needs to be raised so women can unobtrusively access the ECP.

A comprehensive picture on the mechanism of the epoxy-phenol curing reactions is presented using the density functional theory B3LYP/ 6-31G(d,p) and simplified physical molecular models to examine all possible reaction pathways. Phenol can act as its own promoter by using an addition phenol molecule to stabilize the transition states, and thus lower the rate-limiting barriers by 27.0-48.9 kJ/mol. In the uncatalyzed reaction, an epoxy ring is opened by a phenol with an apparent barrier of about 129.6 kJ/mol. In catalyzed reaction, catalysts facilitate the epoxy ring opening prior to curing that lowers the apparent barriers by 48.9-50.6 kJ/mol. However, this can be competed in highly basic catalysts such as amine-based catalysts, where catalysts are trapped in forms of hydrogen-bonded complex with phenol. Our theoretical results predict the activation energy in the range of 79.0-80.7 kJ/mol in phosphine-based catalyzed reactions, which agrees well with the reported experimental range of 54-86 kJ/mol.

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