1 Then, menthol was achieved from citronellal by two-step reaction, with the yield of the compound of each step is to 90%.

2 Study progress on cyclization of citronellal to(-)-isopulegol over catalysts is reviewed.

3 On the perfume industry at present, citronellol is prepared from oil of citronellal and geraniol.

4 The results suggest that in the medium eight kinds of moulds, antibiotic activities in turn decrease on citral, citronellal, litsea cubeba oil, geraniol, linalool and methyl heptenone at a pH of 4.5.

5 The review focuses on the different catalysts and craft on the hydrogenation of the major terpene: pinene, dipentene, citronellal citral, geraniol etc over catalysts and craft.