Studies on intramolecular alkylation. II. The preparation of intermediates for diterpene synthesis by intramolecular carbenoid addition reactions

1972 ◽  
Vol 25 (1) ◽  
pp. 137 ◽  
Author(s):  
DJ Beames ◽  
JA Halleday ◽  
LN Mander
Keyword(s):  
New Method ◽  
Addition Reactions ◽  
Dilute Acid ◽  
Ring Systems ◽  
Intramolecular Alkylation ◽  
Tricyclic Compounds ◽  
Cyclopropyl Ketones ◽  
Diazomethyl Ketones

A new method is described for the preparation of tricyclic compounds containing the 3,2,1- and 2,2,2-bicyclooctane ring systems. The copper-catalysed decomposition of the diazomethyl ketones derived from the olefinic acids (7), (9), (18), and (19) afforded, respectively, the cyclopropyl ketones (12), (13), (21), and (20). These compounds were transformed into the cyolopropyl diketones (15) and (22) which by treatment with dilute acid or base gave, in turn, the bridged octalones (1) and (2).

Studies on intramolecular alkylation. XIV. The preparation of methoxylated cyclohexadienone derivatives from intramolecular diazoketone cyclizations inrelationship to isoquinoline alkaloid synthesis

1981 ◽  
Vol 34 (6) ◽  
pp. 1243 ◽  
Author(s):  
DW Johnson ◽  
LN Mander ◽  
TJ Masters
Keyword(s):  
Trifluoroacetic Acid ◽  
Isoquinoline Alkaloid ◽  
Intramolecular Alkylation ◽  
Alkaloid Synthesis ◽  
Tricyclic Compounds ◽  
Wide Range ◽  
Diazomethyl Ketones

A series of di- and tri-methoxytetrahydronaphthyl diazomethyl ketones (4), (6), (8), (25) and (27) have been prepared and cyclized in trifluoroacetic acid. A wide range of methoxylated cyclohexa- dienone containing tricyclic compounds (12), (15), (17), (18) and (30) were obtained as well as several rearranged derivatives, i.e. (13), (14), (32) and (33).

A new method of introducing the angular methyl group into fused ring systems

1969 ◽  
Vol 10 (7) ◽  
pp. 561-564 ◽  
Author(s):  
James J. Sims ◽  
L.H. Selman
Keyword(s):  
New Method ◽  
Ring Systems ◽  
Methyl Group ◽  
Fused Ring

Studies on intramolecular alkylation. X. The acid-catalysed reactions of 5,8-Dialkoxy-1,2,3,4-tetrahydronaphthyl diazomethyl ketones

1978 ◽  
Vol 31 (7) ◽  
pp. 1561 ◽  
Author(s):  
DW Johnson ◽  
LN Mander
Keyword(s):  
Trifluoroacetic Acid ◽  
Acid Treatment ◽  
Polyphosphoric Acid ◽  
Intramolecular Alkylation ◽  
Naphthoic Acid ◽  
Acid Catalysed Reactions ◽  
Diazomethyl Ketones

5,8-Dimethoxy-3,4-dihydronaphthalen-1(2H)-one was converted into diazomethyl 5,8-dimethoxy-1,2,3,4-tetrahydro-2-naphthyl ketone (10) which, when treated with trifluoroacetic acid at 0°, gave 5,8- dimethoxy-4,4a-dihydro-3,4a-ethanonaphthalen-2(3H)-one (13), but at -15° gave 8-methoxy-1,2,3,4-tetrahydro-3,4a-ethanonaphthalene- 5(4aH),10-dione (14). 6-Methoxy-3,4-dihydronaphtha-len-1(2H)-one reacted with m-chloroperoxybenzoic acid to give 4,5-dihydro-1-benzoxepin-2(3H)-one (15) which after hydrolysis, ethylation and polyphosphoric acid treatment gave 5-ethoxy-8-methoxy-3,4-dihydronaphthalen-1(2H)-one (17). This compound was transformed into 5-ethoxy-8-hydroxy-1,2,3,4-tetrahydro-2-naphthoic acid (19) and thence to the ethoxy analogue of (14).

A new method for the synthesis of fused 3-amino-s-triazole ring systems

1978 ◽  
Vol 15 (2) ◽  
pp. 311-312 ◽  
Author(s):  
Yang-i Lin ◽  
T. L. Fields ◽  
S. A. Lang
Keyword(s):  
Triazole Ring ◽  
New Method ◽  
Ring Systems

Photoreactions of Tricyclic α-Cyclopropyl Ketones and Unsaturated Enones – Synthesis of Polyquinanes and Analogous Ring Systems

2006 ◽  
Vol 2006 (2) ◽  
pp. 351-370 ◽  
Author(s):  
Nikolay T. Tzvetkov ◽  
Beate Neumann ◽  
Hans-Georg Stammler ◽  
Jochen Mattay
Keyword(s):  
Ring Systems ◽  
Cyclopropyl Ketones

ChemInform Abstract: A New Method for the Preparation of the 6,6 and 6,7 Ring Systems of Bicyclic Ethers.

ChemInform ◽  
2010 ◽  
Vol 30 (9) ◽  
pp. no-no
Author(s):  
F. SIMART ◽  
Y. BRUNEL ◽  
S. ROBIN ◽  
G. ROUSSEAU
Keyword(s):  
New Method ◽  
Ring Systems

Synthetic Studies of Daphniphyllum Alkaloids: A New Method for the Construction of [7-5-5] All-carbon Tricyclic Skeleton

Synlett ◽  
2021 ◽  
Author(s):  
Jun-ichiro Kishi ◽  
Kazutada Ikeuchi ◽  
Takahiro Suzuki ◽  
Keiji Tanino
Keyword(s):  
Molecular Structure ◽  
Michael Addition ◽  
New Method ◽  
Alkylation Reaction ◽  
Intramolecular Alkylation ◽  
Tricyclic Core ◽  
Synthetic Studies ◽  
Cyclopentadienyl Anion ◽  
Anion Species ◽  
Phenyl Vinyl

Daphniphyllum alkaloids have a complex molecular structure; thus, their synthesis can be challenging. A new method for the construction of the [7-5-5] tricyclic core of Daphniphyllum alkaloids was developed. The bicyclo[5.3.0]decane skeleton was constructed via the divinylcyclopropane rearrangement of a cyclopentenone derivative with a vinylcyclopropyl group at the β-position. After introducing a 2-iodoethyl group via a regioselective Michael addition with phenyl vinyl selenone, the [7-5-5] tricyclic system was formed by the intramolecular alkylation reaction of a cyclopentadienyl anion species.

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