Doc Brown's GCE Chemistry
Revising Advanced Level Organic Chemistry
GCE A Level Revision Notes PART 10 Summary of organic reaction mechanisms
A mechanistic introduction to organic chemistry and explanations of different types of organic reactions
10.6.2 Reaction with hydrogen cyanide
Examples are explained of the organic chemistry mechanisms for aldehydes and ketones undergoing nucleophilic substitution, nucleophilic addition reactions are described with diagrams and full explanation revision notes. Carbonyl compounds – ALDEHYDES and KETONES – introduction, Nucleophilic addition of hydrogen cyanide to form a hydroxy–nitrile. The revision notes include full diagrams and explanation of the mechanisms and the 'molecular' equation and reaction conditions and other con–current reaction pathways for these reactions of aldehydes and ketones and products are also explained.
10.6 Carbonyl compounds – ALDEHYDES and KETONES
10.6.1 Introduction to aldehyde and ketone reactivity
Aldehydes and ketones readily undergo nucleophilic attack because of the highly polar carbonyl bond >Cδ+=Oδ– caused by the big difference in the electronegativity between carbon (2.5) and oxygen (3.5). An electron pair donating nucleophile (Nuc:), will therefore attack the 'positive carbon' (Cδ+) to form a C–Nuc bond. A comparison of electrophilic addition to alkenes with nucleophilic addition to aldehydes/ketones is included in these notes.
10.6.2 Nucleophilic addition of hydrogen cyanide to aldehydes or ketones to give hydroxy–nitriles
The organic synthesis of hydroxynitriles from the reaction of cyanide with aldehydes and ketones
mechanism 7 – nucleophilic addition of cyanide ion to an aldehyde or ketone
nucleophilic addition RR'C=O + HCN ==> RR'C(OH)CN
APPENDIX - COMPLETE MECHANISM and Organic Synthesis INDEX (so far!)