117471-21-3

Basic information

• Product Name: (1S,6R,7R,8R)-3-Methoxy-7-methyl-8-phenyl-bicyclo[4.2.0]oct-3-ene-2,5-dione
• CAS NO: 117471-21-3
• Molecular Weight: 256.301
• Mol File: 117471-21-3.mol
• Article Data: 4

Chemical Properties

• CAS DataBase Reference: (1S,6R,7R,8R)-3-Methoxy-7-methyl-8-phenyl-bicyclo[4.2.0]oct-3-ene-2,5-dione(CAS DataBase Reference)
• NIST Chemistry Reference: (1S,6R,7R,8R)-3-Methoxy-7-methyl-8-phenyl-bicyclo[4.2.0]oct-3-ene-2,5-dione(117471-21-3)
• EPA Substance Registry System: (1S,6R,7R,8R)-3-Methoxy-7-methyl-8-phenyl-bicyclo[4.2.0]oct-3-ene-2,5-dione(117471-21-3)

Safety Data

• Hazardous Substances Data: 117471-21-3(Hazardous Substances Data)

Upstream product

• 873-66-5 1-propenylbenzene 
• 2880-58-2 2-methoxy-1,4-benzoquinone 
• 637-50-3 1-phenylpropene 
• 766-90-5 cis-1-phenyl-1-propylene 
• 90-05-1 2-methoxy-phenol 

Downstream Products

• 21008-39-9 (2R,3S)-6-Methoxy-3-methyl-2-phenyl-2,3-dihydro-benzofuran-5-ol 
• 21008-39-9 (+/-)-Obtusafuran 

Relevant articles and documents

Asymmetric reactions of 2-methoxy-1,4-benzoquinones with styrenyl systems: Enantioselective syntheses of 8-aryl-3-methoxybicyclo[4.2.0]oct-3- en-2,5-diones, 7-Aryl-3-hydroxybicyclo[3.2.1]oct-3-en-2,8-diones, 2-Aryl-6- methoxy-2,3-dihydrobenzofuran-5-ols, and pterocarpans

Reactions of 2-methoxy-1,4-benzoquinones 2 and 3 with (E)- propenylbenzenes 1 promoted at -78 °C by Ti(IV)-TADDOLates prepared from diol-(+)-4 afford (1R,6R,7R,8R)-8-aryl-3-methoxy-7-methylbicyclo[4.2.0]oct- 3-en-2,5-diones 5/8 or (1R,5R,6R,7R)-7-aryl-3-hydroxy-6-methylbicyclo[3.2.1]- oct-3-en-2,8-diones 7/10 in good yield and high ee. (2S,3S)-2-Aryl-6-methoxy- 3-methyl-2,3-dihydrobenzofuran-5-ols 6/9 are also found, but in slightly lower ee. Cyclobutanes 5/8 cleanly and efficiently rearrange to the dihydrobenzofurans 6/9 without loss of enantiomeric purity upon treatment with the Ti-TADDOLates at higher temperatures. Reactions of (Z)- propenylbenzene 17 and of indene with 2 and 3 give products in moderate enantiomeric purity. Products obtained from reactions of 1-anisylcycloalkenes with 2 differ significantly in yield and enantiomeric purity. In the latter reactions, the ee's of the cyclobutane products are consistently much higher than those of the dihydrobenzofuran products. More significantly, products of different absolute configuration result from different cycloalkenes. With 1- anisylcyclopentene or 1-anisylcyclohexene, all of the products are of similar configuration and are obtained in comparable yields and ee's. However, 1- anisylcycloheptene affords products that are diastereomeric with those of the 1-anisylcyclopentene, and in lower ee's. A mechanistic model is proposed. Application of these reactions to the enantioselective synthesis of the pterocarpan class of isoflavonoid natural products is also reported.

Selective Control of the Various Cycloaddition Products from Reactions of Styrenes and 1,4-Benzoquinones: Optimization of the Formal 5 +2 Cycloadducts

7-Aryl-3-hydroxy-6-methylbicyclooct-3-ene-2,8-diones 4 and 8 are formed exclusively in Ti(IV)-catalyzed reactions of 2-((4-methoxybenzyl)oxy)-1,4-benzoquinones 5a/d with trans-β-methylstyrene and indene, resprectively.