Sumários
Some general synthetic methods
2 Novembro 2016, 14:00 • Christopher David Maycock
Synthesis of amines using azides. Protecting groups for hydroxyls (acetate,benzyl, THP) normally to prevent O-nucleophilicity and eliminate the acidity of OH groups. Protecting groups for amines to prevent reactions of the nitrogen atom using carbamates. Deprotection methods. acid hydrolysis of acetals, hydrogenolysis of benzyl groups or benzyl carbamates, acid removal of tet-Bu group from esters and carbamates. Silyl protecting groups and their removal with fluoride. Bulky and less reactive silyl groups for acid and base resistance during functional group and C_C-bond forming reactions.
Continuation of block 1 experiments.
26 Outubro 2016, 16:00 • Christopher David Maycock
See list of experiments carried out in rotation by group.
An alternative Thienamycin synthesis
26 Outubro 2016, 14:00 • Christopher David Maycock
Completion of the enantioselective synthesis and presentation of a racemic but highly stereoslective synthesis from inexpensive starting materials.
Practical class
19 Outubro 2016, 16:00 • Christopher David Maycock
Continuation of block 1 experiments with group 2 (Before the previous class the students were divided into 2 groups to avoid the presence of an excessive numbers of students creating a safety hazard and operational impossibility).
Capnellene and Thienamycin
19 Outubro 2016, 14:00 • Christopher David Maycock
Amine bases, tertiary amines, amidines, guanidines. Stability of ammonium ion and steric hindrance factors determining basicity and nucleophilicity. Effect of temperature on basicity/nuclophilicity in general. Protection of aldehydes against organometallic reagents and reducing agents. Cr(VI) reagents for the formation of aldehydes from alcohols (anhydrous) and the Jones oxidation (presence of watering acid) to carboxylic acid directly from an aldehyde acetal. Diazomethane for the direct formation of methyl esters from carboxylic acids. Reaction of esters with organometallic reagents (e.g. Grignard) and the formation of tertiary alcohols. Formation of tertiary halides with acid halides (carbocations).