Bobbitt reaction

The Bobbitt reaction is a name reaction in organic chemistry . It was published in 1965 by James M. Bobbitt (* 1930). R. Quelet and N. Vinot also studied this chemistry.

Overview reaction

In the Bobbitt reaction, 1,2,3,4-tetrahydroisoquinoline is produced in a reaction from benzaldehyde and 2,2-diethoxyethylamine:

Reaction mechanism

In the proposed reaction mechanism, benzaldehyde 1 initially reacts with 2,2-diethoxyethylamine 2 . By splitting off water , intermediate 3 is formed , which reacts to benzylamino acetal 4 by hydrogenation . In the presence of hydrochloric acid, a cyclocondensation reaction of the substituted benzylaminoacetal 4 takes place , and the enamine 5 is formed through renewed elimination of water . Hydrogenation of the C = C double bond gives 1,2,3,4-tetrahydroisoquinoline 6 .

modification

The Bobbitt reaction is not limited to the synthesis of 1-substituted isoquinolines; 4- and N -substituted isoquinoline derivatives can also be prepared in this way.

application

The Bobbitt reaction is used in the synthesis of 1-, 4- and N -substituted 1,2,3,4-tetrahydroisoquinolines. In addition, 1- and 4-substituted isoquinolines and alkaloids such as salsolin, salsolidine, carnegine and lophocerin can be produced.

Individual evidence

↑ ^a ^b ^c ^d Zerong Wang: Comprehensive Organic Name Reactions and Reagents . John Wiley & Sons, Inc., Hoboken, NJ, USA 2010, ISBN 978-0-470-63885-9 , doi : 10.1002 / 9780470638859 .
↑ JM Bobbitt, Judith McNew Kiely, KL Khanna, R. Ebermann: Synthesis of Isoquinolines. III. A New Synthesis of 1,2,3,4-Tetrahydroisoquinolines 1 . In: The Journal of Organic Chemistry . tape 30 , no. 7 , July 1, 1965, p. 2247-2250 , doi : 10.1021 / jo01018a030 .
^ Antonio Rodriguez-Antunez, Frank R. Hendrickson, David H. Hussey, George E. Laramore, Roger Davis: Fast neutron irradiation of metastatic cervical adenopathy: The results of a randomized RTOG study . In: International Journal of Radiation Oncology • Biology • Physics . tape 9 , no. 9 , September 1, 1983, pp. 1267-1270 , doi : 10.1016 / 0360-3016 (83) 90256-0 , PMID 6350243 ( redjournal.org [accessed May 28, 2019]).
↑ James M. Bobbitt, Dibyendu Nath Roy, Anthony Marchand, Christopher Whitney Allen: Synthesis of isoquinolines. VI. N-alkyl-1,2,4-tetrahydroisoquinolines . In: The Journal of Organic Chemistry . tape 32 , no. 7 , July 1, 1967, p. 2225-2227 , doi : 10.1021 / jo01282a030 .
↑ JM Bobbitt, Tsu-Teh Chou: Synthesis of Isoquinoline Alkaloids. I. Lophocerine 1 . In: The Journal of Organic Chemistry . tape 24 , no. 8 , August 1, 1959, p. 1106-1108 , doi : 10.1021 / jo01090a018 .

[:0-1] Zerong Wang: Comprehensive Organic Name Reactions and Reagents . John Wiley & Sons, Inc., Hoboken, NJ, USA 2010, ISBN 978-0-470-63885-9 , doi : 10.1002 / 9780470638859 .

[2] JM Bobbitt, Judith McNew Kiely, KL Khanna, R. Ebermann: Synthesis of Isoquinolines. III. A New Synthesis of 1,2,3,4-Tetrahydroisoquinolines 1 . In: The Journal of Organic Chemistry . tape 30 , no. 7 , July 1, 1965, p. 2247-2250 , doi : 10.1021 / jo01018a030 .

[3] Antonio Rodriguez-Antunez, Frank R. Hendrickson, David H. Hussey, George E. Laramore, Roger Davis: Fast neutron irradiation of metastatic cervical adenopathy: The results of a randomized RTOG study . In: International Journal of Radiation Oncology • Biology • Physics . tape 9 , no. 9 , September 1, 1983, pp. 1267-1270 , doi : 10.1016 / 0360-3016 (83) 90256-0 , PMID 6350243 ( redjournal.org [accessed May 28, 2019]).

[4] James M. Bobbitt, Dibyendu Nath Roy, Anthony Marchand, Christopher Whitney Allen: Synthesis of isoquinolines. VI. N-alkyl-1,2,4-tetrahydroisoquinolines . In: The Journal of Organic Chemistry . tape 32 , no. 7 , July 1, 1967, p. 2225-2227 , doi : 10.1021 / jo01282a030 .

[5] JM Bobbitt, Tsu-Teh Chou: Synthesis of Isoquinoline Alkaloids. I. Lophocerine 1 . In: The Journal of Organic Chemistry . tape 24 , no. 8 , August 1, 1959, p. 1106-1108 , doi : 10.1021 / jo01090a018 .