Patent ID: 7550633

Claim:
A process for preparing isopulegol having the formula (I) comprising the step of cyclizing citronellal having the formula (II) in the presence of (a) a tris(aryloxy)aluminum catalyst having the formula (III) wherein Al is aluminum, R 1 , R 2 and R 3 identically or differently are hydrogen; halogen; alkyl having up to 8 carbon atoms; alkoxy having up to 8 carbon atoms; substituted or unsubstituted aryl; dialkylamino, wherein each alkyl can have up to 4 carbon atoms; or nitro; and R 4 and R 5 identically or differently are halogen, alkyl having up to 8 carbon atoms, alkoxy having up to 8 carbon atoms, dialkylamino, wherein each alkyl can have up to 4 carbon atoms; nitro; substituted or unsubstituted aryl; or substituted or unsubstituted heteroaryl; (b) at least one acid; and/or (c) at least one of carboxylic anhydrides, aldehydes, ketones, and vinyl ethers.