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Why cumulenes have planarity while allens does not have?
why cumulenes have planarity while allens does not have?
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Dinesh khalmaniya 1
check it. allene have two double bonds. so if molecule have even doubles bonds are non planar. while cumulese have more than 3 double bonds. so if cumulese have odd double bond than it is planar otherwise non planar
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Suman Kumar
Remember this trick if double bond comes to even then Compound is non-planar.
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And if no. of double bond is odd then Compound will be planar
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A cumulene is a hydrocarbon with three or more cumulative (consecutive) double bonds.[1] They are analogous to allenes, only having a more extensive chain. The simplest molecule in this class is butatriene (H 2C=C=C=CH 2), which is also called simply cumulene.
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Remember in both case double bond must be consecutive.
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See this for Allene bonding. So it is non planar
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Dinesh khalmaniya 1
hope this will help you 🙏🙏
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so non planar molecule show stereoisomeris
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both planar and non planar show stereoisomerism
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planar molecule show GI while non planar molecule show OI
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ys
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is this the same case with spiranes and hemispiranes
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yes same case
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rings works just like double bonds. so no difference.
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Dinesh khalmaniya 1
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A cumulene is a hydrocarbon with three or more cumulative double bonds. They are analogous to allenes, only having a more extensive chain. allene have two double bonds so it is non planar. while in cumulenes have even no. of double bonds are non plalar while oddd no. of double bonds are planar
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Priyanshu kumar![best-answer]()
If no. of pi bonds even then non planar if odd then planar
A cumulene is a hydrocarbon with three or more cumulative (consecutive) double bonds.[1] They are analogous to allenes, only having a more extensive chain. The simplest molecule in this class is butatriene (H 2C=C=C=CH 2), which is also called simply cumulene.
Hope this will helps u😊🙏
Allenes here show Optical isomerism