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Date: 19-9-2019
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Date: 15-5-2017
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For straight chain alkenes, it is the same basic rules as nomenclature of alkanes except change the suffix to "-ene."
In this diagram this is a cis conformation. It has both the substituents going upward. This molecule would be called (cis) 5-chloro-3-heptene.)
Trans would look like this
v. On the other hand if there are 3 or 4 non-hydrogen different atoms attached to the alkene then use the E, Z system.
E (entgegen) means the higher priority groups are opposite one another relative to the double bond.
Z (zusammen) means the higher priority groups are on the same side relative to the double bond.
(You could think of Z as Zame Zide to help memorize it.)
In this example it is E-4-chloro-3-heptene. It is E because the Chlorine and the CH2CH3 are the two higher priorities and they are on opposite sides.
vi. A hydroxyl group gets precedence over th double bond. Therefore alkenes containing alchol groups are called alkenols. And the prefix becomes --enol. And this means that now the alcohol gets lowest priority over the alkene.
vii. Lastly remember that alkene substituents are called alkenyl. Suffix --enyl.
Here is a chart containing the systemic name for the first twenty straight chain alkenes.
Name | Molecular formula |
Ethene | C2H4 |
Propene | C3H6 |
Butene | C4H8 |
Pentene | C5H10 |
Hexene | C6H12 |
Heptene | C7H14 |
Octene | C8H16 |
Nonene | C9H18 |
Decene | C10H20 |
Undecene | C11H22 |
Dodecene | C12H24 |
Tridecene | C13H26 |
Tetradecene | C14H28 |
Pentadecene | C15H30 |
Hexadecene | C16H32 |
Heptadecene | C17H34 |
Octadecene | C18H36 |
Nonadecene | C19H38 |
Eicosene | C20H40 |
Did you notice how there is no methene? Because it is impossible for a Carbon to have a double bond with nothing.
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الآثار الجانبية لأدوية تستخدم في علاج "ألزهايمر" تثير الجدل
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اكتشاف سر نجاة "مخلوقات أبدية" من انفجارات الإشعاع القاتلة
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موكب أهالي كربلاء يهدي ممثل المرجعية العليا درعا تثمينا للمساهمات الفاعلة والمساندة لإنجاح الفعاليات التي يقيمها خلال المناسبات الدينية
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مراحل متقدمة من الإنجاز يشهدها مشروع مركز الشلل الدماغي في بابل
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الأمين العام للعتبة الحسينية المقدسة: يجب الاهتمام بالباحثين عن العمل ومنحهم الفرص المناسبة عبر الاهتمام بقدراتهم ومؤهلاتهم وإبداعاتهم
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يمتد على مساحة (500) دونم ويستهدف توليد الطاقة الكهربائية.. العتبة الحسينية تعلن عن الشروع بإنشاء مشروع معمل لتدوير النفايات في كربلاء
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