please ,this link maybe help you

https://en.wikipedia.org/wiki/Lactone

The C=C bond in the "lactone" of flavone is not a normal C=C bond (it's in an extended π system), so reducing it will be harder. Some people have done it using NaBH4 and a transition metal like nickel or cobalt, producing the desired compound in

Pratibha

I agree with Aaron, the C=C is part of conjugated system with C=O and can be reduced using NaBH4

* n mmol of substrate in  methanol and 5n mmol of NiCl26H2O placed in a round bottomed flask attached to a reflux condenser and mounted over a magnetic stirrer. The contents of the flask were stirred magnetically and NaBH4 (5n mmol) was added to the flask. Thereafter, lots of NiCl26H2O (5n mmol) and NaBH4 (5n mmol) were added at intervals of 2 h until the starting material completely disappeared  as observed by TLC. 

See

--- Khurana, Jitender Mohan and Sharma, Purnima, Bulletin of the Chemical Society of Japan, 77(3), 549-552; 2004

If you are looking for stereoselective reduction, see

--- Zhao, Dongbing et al.,  Ruthenium-NHC-Catalyzed Asymmetric Hydrogenation of Flavones and Chromones: General Access to Enantiomerically Enriched Flavanones, Flavanols, Chromanones, and Chromanols  Angewandte Chemie, International Edition, 52(32), 8454-8458; 201

Good luck

I do agree with the above discussion.

If you have a chance try this Photochemical method, please read this paper

"Photochemical Synthesis of 2,2¢-Biflavanones from Flavone"

They just tried with acetonitrile and triethylamine and other conditions are in this paper.

From this reaction you will get racemate and the required compound.

Few other references which are very good.

1. Efficient cobalt(II) phthalocyanine-catalyzed reduction of flavones with sodium borohydride

2. Chemoselective Reduction of α,β-Unsaturated Aldehydes, Ketones, Carboxylic Acids, and Esters with Nickel Boride in Methanol–Water.

Good Luck.

I also do agree with above. You can also try to use strong hydride sources such as DIBAL. I just have found a several interesting papers describing the use of DIBAL for reduction of C=C bond in flavone moiety.

Journal of Medicinal Chemistry, 2016 , vol. 59, # 22 p. 10228 - 10243

Synthesis, 1981 , # 7 p. 574 - 576

Russian Chemical Bulletin, 2009 , vol. 58, # 12 p. 2465 - 2473

I suppose that the reaction should be conducted at low temperature (~-60 - -70 C) to ensure good chemoselectivity (side reduction of the ketone moiety).

http://www.columbia.edu/cu/chemistry/groups/nakanishi/publication/760-%20Lactone-free%20ginkgolides%20via%20regioselective%20DIBAL-H%20reduction.pdf

USE ABOVE LINK TO FIND ANS.IT MAY BE USEFUL

Dear Adel Amer

I tried using the method suggested by you but it didn't work always we got starting back.. if any new method please suggest me.

With regards

Pratibha

n mmol of substrate in  methanol and 5n mmol of NiCl26H2O placed in a round bottomed flask attached to a reflux condenser and mounted over a magnetic stirrer. The contents of the flask were stirred magnetically and NaBH4 (5n mmol) was added to the flask. Thereafter, lots of NiCl26H2O (5n mmol) and NaBH4 (5n mmol) were added at intervals of 2 h until the starting material completely disappeared  as observed by TLC.

See

--- Khurana, Jitender Mohan and Sharma, Purnima, Bulletin of the Chemical Society of Japan, 77(3), 549-552; 2004

Strong reducing agent for double bond of lactone ring of flavone moiety?. Available from: https://www.researchgate.net/post/strong_reducing_agent_for_double_bond_of_lactone_ring_of_flavone_moiety [accessed Apr 24, 2017].