Convenient one-pot synthesis of 4,8-dimethyl-bicyclo[3.3.1]non-7-en-2-ol via platinum/tin catalyzed hydroformylation/cyclization of limonene

Synthesis of Fragrance Ingredients by Tandem Hydroformylation‐Cyclization of Limonene Catalyzed by Rhodium Complexes and Pyridinium p‐Toluenesulphonate

“…Recently, we have reported the tandem rhodium‐catalyzed hydroformylation‐acetalization of para ‐menthenic terpenes, including limonene ( 1 ), which gives acetals in a direct one‐pot process 12. Another example of tandem transformations of limonene under the hydroformylation conditions we have found, used PtCl 2 /phosphine (diphosphine)/SnCl 2 combinations as the catalyst 13. In these systems, the primarily formed aldehyde ( 2 ) undergoes an intramolecular in situ cyclization giving a bicyclic alcohol, 4,8‐dimethyl‐bicyclo[3.3.1]non‐7‐en‐2‐ol ( 3 ).…”

“…Terpenes are an important biomass‐based renewable feedstock for the flavor and fragrance industries 4–6. For several years, we have been interested in the hydroformylation of terpenes 7–13. In particular, efforts have been made to combine hydroformylation with other reactions which can provide attractive and economic entries to a wide variety of important fine chemicals.…”

Organometallic Catalysis: Some Contributions to Organic Synthesis

“…has been achieved with PtCl 2 (PhCN) 2 /SnCl 2 /diphosphine catalysts containing chiral diphosphines such as (R)-(+)-binap (2,2'-bis(diphenylphosphino)-1,1'-binaphthyl) 48 . Under hydroformylation conditions limonene can be converted in one pot into bicyclic alcohol 30, useful as perfume, employing the PtCl 2 (dppb)/PPh 3 /SnCl 2 bifunctional catalyst, which promotes both the hydroformylation of 1 and then the stereospecific intramolecular cyclization of menthene (29) 45 . At 130 °C, 30 becomes the dominant product (ca.…”

Organometallic catalysis: some contributions to organic synthesis

“…Among the alternative catalytic systems, those based on platinum/tin compositions are probably the most promising ones, as these systems allow high regioselectivity for the formation of linear aldehydes and are especially efficient in asymmetric reactions. However, their applications to monoterpenes are scarcer [43][44][45][46] . We studied the hydroformylation of β-pinene (Scheme 12) using rhodium complexes and various phosphines and diphosphines as auxiliaries 47 .…”