Otera's catalyst
Chemical compound
From Wikipedia, the free encyclopedia
Otera's catalyst, named after Japanese chemist Junzo Otera, is an organostannane compound which has been used as a transesterification catalyst. This isothioscyanate compound is a member of a family of organostannanes reported by Wada and coworkers,[1] and elaborated upon by Otera and coworkers.[2]
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| Other names
Octabutyltetrathiocyanatostannoxane | |
| Identifiers | |
3D model (JSmol) |
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| Properties | |
| C36H72N4O2S4Sn4 | |
| Molar mass | 1196.08 g·mol−1 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Preparation
This class of compounds may be prepared generally by the reaction of an organotin halide and oxide:[3]
- 2 R2SnO + 2 R2SnX2 → (XR2SnOSnR2X)2
In particular, the thiocyanate compound was prepared by the reaction of dibutyltin oxide with dibutyltin diisothiocyanate.[1] Otherwise, this compound is not commercially available.
Applications
This thiocyanate compound can be used as a transesterification catalyst.[2] Although it is not well known, it has been used in a number of total syntheses.[4][5]
In this application, the reaction occurs via the displacement of the bridging isothiocyanate ligands with the incoming alcohol to form an alcohol-bridged active catalyst. Tin acts as the Lewis acid, and gives the transesterified product.[2][3] The reaction must be performed in nonpolar solvents in order to colocate the acid and alcohol at the catalytic center.[6]