, Hive-unknown? : Beilstein reaction possibilities. Hive Methods Discourse
 
    3base
(Stranger)
02-07-02 10:51
No 266531
      Hive-unknown? : Beilstein reaction possibilities.
(Rated as: excellent)
 Bookmark   

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piperonylalcohol --> piperonal

Reagent: MnO2, molecular sieves; Solvent hexane;
Time 2h; Heating; Yield given

J.Chem.Res.Synop.; EN; 6; 1998; 308-309;
Hirano, Masao; Yakabe, Sigetaka; Chikamori, Hideki;
Clark, James H.; Morimito, Takashi
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piperonylalcohol --> piperonal

Reagent: MnO2 (CMD); Solvent CH2Cl2; Time 24h;
Ambient temperature; Yield 95%

Syn.Lett.; EN; 1; 1998; 35-36;
Journal; Aoyama, Toyohiko; Sonoda, Naoko; Yamauchi,
Mariko; Toriyama, Kyoko; Anzai, Masahiro; et al.
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piperonylalcohol --> piperonal

Solvent CH2Cl2; Time 3h; Yield: 96%

J.Chem.Soc.Dalton Trans.; EN; 1989; 901-906;
El-Hendawy, Ahmed M.; Griffith, William P.;
Taha, Fatma I.; Moussa, Mahmoud N.
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piperonylalcohol --> piperonal

Reagent H2O2; Catalyst: ligninase; Ambient temperature;
pH 3.0; Subject Studied; Product distribution

Phytochemistry; EN; 30; 1; 1991; 121-126;
Ageorges, Agnes; Pelter, Andrew; Ward, Robert S.
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demorol
(Hive Bee)
02-06-02 15:55
No 266091
         Re: piperonylalcohol --> piperonal 
I'm sure all these syntheses work, but the piperonylalcohol is not very easy to get.
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Life without chemistry would be a mistake.
 

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benzylchloride --> benzaldehyde

Reactant: hexamethylenetetramine

J.Chem.Soc.; 1949; 2704; Angyal et al.

C.R.Hebd.Seances Acad.Sci.; 157; 1913; 852; Sommelet

Patent DE 268786; Fabr. de Laire
Fortschr.Teerfarbenfabr.Verw.Industriezweige; DE; GE; 11; 197
------------------------------------------------------------------------------
benzylchloride --> benzaldehyde

Reactant: aqueous Ca(NO3)2 solution

Zh.Prikl.Khim.(Leningrad); 3; 1930; 721, 725; Schorygin; Kisber; Ssmoljaninowa

Chem.Zentralbl.; GE; 101; II; 1930; 3397
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benzylchloride --> benzaldehyde

Reagent: diluted nitric acid   or   aqueous lead nitrate

Lauth; Grimaux; Bull.Soc.Chim.Fr.; <2> 7; 1867; 106
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benzylchloride --> benzaldehyde

Reagent: copper nitrate
Other Conditions: Reaktion ueber mehrere Stufen

Book Review / Secondary Ref.; Fischer,E.; Anleitung zur Darstellung
organischer Praeparate,  9. Aufl. <Braunschweig 1920>, S. 41
------------------------------------------------------------------------------
benzylchloride --> benzaldehyde

Reactant: potassium nitrite
anthracene; Temperature: 150 C

Chem.Ber.; 9; 1876; 1745; Brunner
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benzylchloride --> benzaldehyde

Reactant: nickel-powder, air ; Temperature: 160 C

Korczynski; Reinholz; Schmidt; ROCHAC; Rocz.Chem.; 9; 1929; 731,738
Chem.Zentralbl.; GE; 101; I; 1930; 2075
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benzylchloride --> benzaldehyde

Reagent: DMSO, NaHCO3

J.Org.Chem.; 24; 1959; 1792; Nace; Monagle
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benzylchloride + benzalchloride --> benzaldehyde

2 C5H5.CH2.Cl + C5H5.CH.Cl2 + 2 MnO2 --> 3 C6H5.CHO + 2 MnCL2 + H2O

Patent DE 20909, Schmidt
Fortschr.Teerfarbenfabr.Verw.Industriezweige; DE; GE; 1; 23
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hi, here are some refs again.
the first with MnO2/Microwaves is very nice.
the first sentence of the description of the procedure is:

" MnO2 'doped' silica ... "

that's music in my ears !

the article doesn't mention how the obtained benzaldehyde was further
treated, but with regard to the writingstyle, i could imagine that
they've done a microwave assisted Knoevenagel condensation and so on ...

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benzylalcohol --> benzaldehyde

Active Manganese Dioxide on Silica: Oxidation of Alcohols
under Solvent-free Conditions Using Microwaves

Abstract:  Alcohols are rapidly and selectively oxidized to the
corresponding carbonyl compounds by silica supported active
manganese dioxide under solvent-free conditions using microwaves.

Tetrahedron Letters, Vol38, Issue 45, Nov-10-1997, 7823-7824;
Varma, Rajender S.; Saini, Rajesh K.; Dahiya, Rajender
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benzylalcohol --> benzaldehyde

silica gel supported ferric nitrate reagent
Solvent hexane; Time 4h; Other Conditions: Heating

Synth.Commun.; EN; 28; 2; 1998; 207-212;
Khadilkar, Bhushan; Borkar, Shobha
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benzylalcohol --> benzaldehyde

Chromat; Reagent MnO2/bentonite; Time 1 min; Temp 175C
Other Conditions: Irradiation; Yield 40%

Tetrahedron Lett.; FR; 34; 33; 1993; 5293-5294;
Martinez, Luis A.; Garcia, Olivia; Delgado, Francisco;
Alvarez, Cecilio; Patino, Rocio
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benzylalcohol --> benzaldehyde

Reagent HBr, H2O2; Solvent CH2Cl2; Time 4h; Temp 60C; Yield 84%

Bull.Soc.Chim.Fr.; EN; 4; 1988; 756; Dakka, Jihad; Sasson, Yoel
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benzylalcohol --> benzaldehyde

Reagent manganese dioxide, benzyl alcohol; Turnov;
Solvent hexane; Temp 20C; Yield 60%

J.Chem.Soc.Perkin Trans.1; EN; 7; 1990; 1937-1943
Cavaleiro, Jose A. S.; Neves, Maria G. P. S.;
Hewlins, Michael J. E.; Jackson, Anthony H.
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    Rhodium
(Chief Bee)
02-08-02 05:43
No 266901
      Re: benzylchloride --> benzaldehyde  Bookmark   

3base: You are doing an excellent work by donating your time in front of Beilstein for our purposes.

Suggested search areas: nitroalkene reductions w/o LAH or catalytic hydrogenation under pressure, ways of making 2,6-dimethoxy-4-bromo-PEA (and other things in the 4-position), phenylacetonitrile and cyanohydrin reductions to phenethylamines, with the same limitations as above.
 
 
 
 
    foxy2
(Distinctive Doe)
02-08-02 11:11
No 267008
      Phenylacetonitrile to phenylethylamine
(Rated as: excellent)
 Bookmark   

Phenylacetonitrile to phenylethylamine Reductions

Reduction of some functional groups with zirconium tetrachloride/sodium borohydride.    
Itsuno, Shinichi; Sakurai, Yoshiki; Ito, Koichi.       
Synthesis  (1988),   (12),  995-6. 
Abstract
A novel reducing agent prepd. from ZrCl4 and NaBH4 reduces various functional groups including C:O, C:N, and C.tplbond.N bonds in excellent yield (85-96%) under mild conditions. 

Supported nickel-catalyzed hydrogenation of aromatic nitriles under low pressure conditions.    
Takamizawa, Satoshi; Wakasa, Noriko; Fuchikami, Takamasa.   
Synlett  (2001),   (10),  1623-1625.
Abstract
Hydrogenation of arom. nitriles takes place under the mild conditions using supported Ni catalysts to afford aminomethyl-substituted aroms. in good yields. 

Convenient synthesis of protected primary amines from nitriles.    
Caddick, Stephen; Haynes, Alexandra K. De K.; Judd, Duncan B.; Williams, Meredith R. V.       
Tetrahedron Lett.  (2000),  41(18),  3513-3516. 
Abstract
Investigations into the use of nickel chloride and sodium borohydride for the redn. of nitriles showed the secondary amine dimers to be the major products under normal conditions.  The addn. of a suitable trapping agent, such as di-tert.-Bu dicarbonate, allowed the isolation of the protected primary amines.

Electrocatalytic reduction of nitriles on Raney nickel.    
Muthukumaran, A.; Krishnan, V.   
Bull. Electrochem.  (1991),  7(9),  410-11.
Abstract
An electrochem. method for the prepn. of primary amines from org. nitriles using a Raney nickel cathode is reported.  It has been obsd. that it is possible to reduce benzyl cyanide to b-phenylethylamine with an yield efficiency of 85% and to reduce benzonitrile to benzylamine with an yield efficiency of 20%.

b-Phenylethylamine by electrolytic reduction of benzyl cyanide using deposited iron black cathode.    
Udupa, Handady Venkatakrishna; Krishnan, Venkatasubramanian; Muthukumaran, Arunachalam.
Indian  (1984),     6 pp. IN  153683  A  19840804
Abstract
In this improved process Fe black cathode deposited an a graphite substrate is used as the cathode in a diaphragm cell.  The catholyte is aq. ethanolic (NH4)2SO4 contg. benzyl cyanide and the anolyte 10% H2SO4.  The anode is a hollow perforated cylinder of Pb-Ag alloy and the reaction vessel is PVC.  Electrolysis was carried out at 5 A/dm2 using 500 A at 10-12 V with a current efficiency of 28% and a yield of 56%.  The use of Fe black cathodes decreased the cost of b-phenylethylamine considerably. 

Fully Informed Jury! (http://www.fija.org/)
 
 
 
 
    3base
(Stranger)
02-09-02 01:52
No 267367
      nitroalkene reductions  Bookmark   

> Suggested search areas: nitroalkene reductions w/o LAH
 > or catalytic hydrogenation under pressure

rhodium: this is exactly what i've searched already some months ago !
for those interessted in catalytic hydrogenation WITHOUT(!)
overpressure under mild conditions, i highly recomend:

"Synthesis of PEA's by Hydrogenation of b-nitrostyrenes"
Bull.Chem.Soc.Jpn., Vol.63, No.4, 1990, pp.1252-1254
Masahiko Hohno, Shigehiro Sasao and Shun-Ichi Murahashi

never fear, it's in english ! a general procedure is
describe using H2, Pd/C and HCl(aq) in EtOH. Stirring
at 0C for 3h followed by a classical workup. they've
prepared several PEA's and their HCL-salts like:
 - mescaline (yield 65%)
 - 3,4-methylenedioxyPEA (yield 71%)

shulgin's alkyloxy-substituted-PEA's like IP, E, ASB are
surley also accessible by this procedure.

it won't get easier wink

Edit: the full article has been uploaded to ../rhodium/chemistry /ns.hydrogenation.html /Rhodium