CH 12-2: Multistep Synthesis

•A series of reactions are required that are written left-to-right as a flow chart:

•We do not balance the reactions.

•Goal is to synthesize (build) a “target” organic compound from smaller, readily available, organic molecules and reagents that are in your “stockroom”.

A E"Target"

compoundStockroom:

A, B, D

BC D

•Reagents are written over the reaction arrows.

•Although this is NOT a mechanism, designing a synthesis does require a knowledge of all reactions we have learned!

Example #1:

•A series of reactions are required that are written left-to-right as a flow chart:•We do not balance the reactions.

•Goal is to synthesize (build) a “target” organic compound from smaller, readily available, organic molecules and reagents that are in your “stockroom”.

•Reagents are written over the reaction arrows.•Although this is NOT a mechanism, designing a synthesis does require a knowledge of all reactions we have learned!

"Target" compound

Stockroom: H2SO4, Br2, NaCN

OH Br

CN

H2SO4 Br2 / NaCN

Example #2:

•A series of reactions are required that are written left-to-right as a flow chart:•We do not balance the reactions.

•Goal is to synthesize (build) a “target” organic compound from smaller, readily available, organic molecules and reagents that are in your “stockroom”.

•Reagents are written over the reaction arrows.•Although this is NOT a mechanism, designing a synthesis does require a knowledge of all reactions we have learned!

"Target" compoundStockroom: H2SO4,

H2O, H2CrO4

O

H2O, H2SO4

OH H2CrO4