Home / Custom Synthesis / Chiral Synthesis / Chiral Auxiliary
BOC Sciences is committed to the synthesis and method development of chiral auxiliaries, and can develop and
produce more high-quality chiral auxiliaries for our customers.
Chiral auxiliary is a compound or unit that is temporarily added to organic synthesis to control the synthesis of
stereochemistry. As the figure below shows, by adding a chiral auxiliary, the prochiral substrate can be
transformed into a chiral product. Moreover, the auxiliary can typically be recycled for future use. As an auxiliary
for chiral synthesis, it must meet the following conditions: the synthesis procedure must be highly stereoselective;
if it is used as raw material, the newly generated chiral center or other chiral elements should be easily separated
from chiral auxiliary without racemization; it should has a high recovery rate without reducing the optical purity.
Fig 1. The mechanism model of chiral auxiliary
Below is a list of our available chiral auxiliaries (include but not limited to the following):
Menthol has 3 chiral centers, so it has 8 stereoisomers. Among these isomers, (-)-menthol has the greatest
industrial value. (-)-Menthol can be purified from natural mint crude oil or can be obtained synthetically.
There are many ways to synthesize (-)-menthol:
1. Synthesis via citronellal Citronellal separated from citronella oil or synthesized from myrcene is easily
cyclized into isopulegol. The (+)-citronellal is cyclized into isopulegol with an acid catalyst, and then the (-)-
rotatory menthol is obtained through the steps of catalytic hydrogenation, rectification, freezing and
2. Synthesized via (-)-menthone (-)-menthol is produced by the reaction of reducing (-)-menthone.
* Services & Products Interested
Please input project description
* Verification Code