CTH: donors and catalysts , Hive Chemistry Discourse

Barium
(Hive Bee)
12-29-02 13:18
No 393795

CTH: donors and catalysts
(Rated as: excellent)

Here is some information about different donors and catalysts for CTH.

Donors

Cyclohexene (Pd)
1,3-Cyclohexadiene (Pd)
1,4-Cyclohexadiene (Pd)
1-Methyloctalin (Pd)
trans-2-Methyloctalin (Pd)
Tetralin (Pd)
1,6-Dimethyltetralin (Pd)
6-Methyltetralin (Pd)
d-Limonene (Pd)
alpha-Pinene (Pd)
beta-Pinene (Pd)
alpha-Phellandrene (Pd)
beta-Phellandrene (Pd)
Terpinolene (Pd)
Cadalene (Pd)
Pulegone (Pd)
Selinene (Pd)
Ethanol (Raney Nickel)
2-Propanol (Raney Nickel)
Methanol (PtCl₂(Ph₃As)₂ + SnCl₂*H₂O)
Diethylcarbinol (Raney Nickel)
Octanol (RuCl₂(Ph₃P)₃)
Cyclohexanol (Raney Nickel)
Benzylalcohol (RuCl₂(Ph₃P)₃)
alpha-Phenylethanol (RuCl₂(Ph₃P)₃)
beta-Phenylethanol (RuCl₂(Ph₃P)₃)
o-Cyclohexylphenol (Pd)
Formic acid, and its salts (almost all catalysts can be used)
Hypophosphorous acid, and its salts (almost all catalysts can be used)

The donor can, in principle, be any organic compound whose oxidation potential is sufficiently low so that the hydrogen transfer can occur under relatively mild conditions. At higher temperatures, especially in the precense of a catalyst, almost any organic compound can donate hydrogen (catalytic cracking), but this has little potential for controlled synthesis.

Reduction of cinnamic acid with various donors

Reaction conditions: 10%w/w 10%Pd/C, refluxing xylene as solvent, if not the donor acts as solvent. Reaction time refers to quantitative conversion to hydrocinnamic acid, unless otherwise noted.

Donor    Solvent Reaction time
p-Menthane    no 16 hours (only trace reduction)
delta1-p-Menthene yes 100 minutes
alpha-Phellandrene    yes 2 minutes
Limonene yes 3 minutes
alpha-Pinene no    300 minutes
beta-Pinene    no    360 minutes
Camphene    no    360 minutes (no reaction)
Tetralin yes    60 minutes
Decalin    no    360 minutes (only trace reduction)

Ref:Chemical reviews, 1974, vol. 74, No 5. 567-580

Catalytic hydrogenation freak


Barium (Hive Bee) 12-29-02 13:18 No 393795	CTH: donors and catalysts (Rated as: excellent)	Bookmark
	Here is some information about different donors and catalysts for CTH. Donors Cyclohexene (Pd) 1,3-Cyclohexadiene (Pd) 1,4-Cyclohexadiene (Pd) 1-Methyloctalin (Pd) trans-2-Methyloctalin (Pd) Tetralin (Pd) 1,6-Dimethyltetralin (Pd) 6-Methyltetralin (Pd) d-Limonene (Pd) alpha-Pinene (Pd) beta-Pinene (Pd) alpha-Phellandrene (Pd) beta-Phellandrene (Pd) Terpinolene (Pd) Cadalene (Pd) Pulegone (Pd) Selinene (Pd) Ethanol (Raney Nickel) 2-Propanol (Raney Nickel) Methanol (PtCl₂(Ph₃As)₂ + SnCl₂H₂O) Diethylcarbinol (Raney Nickel) Octanol (RuCl₂(Ph₃P)₃) Cyclohexanol (Raney Nickel) Benzylalcohol (RuCl₂(Ph₃P)₃) alpha-Phenylethanol (RuCl₂(Ph₃P)₃) beta-Phenylethanol (RuCl₂(Ph₃P)₃) o-Cyclohexylphenol (Pd) Formic acid, and its salts (almost all catalysts can be used) Hypophosphorous acid, and its salts (almost all catalysts can be used) The donor can, in principle, be any organic compound whose oxidation potential is sufficiently low so that the hydrogen transfer can occur under relatively mild conditions. At higher temperatures, especially in the precense of a catalyst, almost any organic compound can donate hydrogen (catalytic cracking), but this has little potential for controlled synthesis. Reduction of cinnamic acid with various donors* Reaction conditions: 10%w/w 10%Pd/C, refluxing xylene as solvent, if not the donor acts as solvent. Reaction time refers to quantitative conversion to hydrocinnamic acid, unless otherwise noted. Donor Solvent Reaction time p-Menthane no 16 hours (only trace reduction) delta1-p-Menthene yes 100 minutes alpha-Phellandrene yes 2 minutes Limonene yes 3 minutes alpha-Pinene no 300 minutes beta-Pinene no 360 minutes Camphene no 360 minutes (no reaction) Tetralin yes 60 minutes Decalin no 360 minutes (only trace reduction) Ref:Chemical reviews, 1974, vol. 74, No 5. 567-580 Catalytic hydrogenation freak