Saturated and Unsaturated Hydrocarbons Saturated hydrocarbons have no double bonds. Unsaturated hydrocarbons have one or more double bonds. 6-אלקנים

Nomenclature of Alkenes Replace “ane” of alkane with “ene.” The functional group gets the lowest possible number. 6-אלקנים 2

Stereoisomers are Named Using a cis or trans Prefix 6-אלקנים

Nomenclature of Dienes two double bonds = diene 6-אלקנים

Nomenclature of Alkenes Number in the direction so that the functional group gets the lowest number. 6-אלקנים

Nomenclature of Alkenes Substituents are stated in alphabetical order. 6-אלקנים

Nomenclature of Alkenes 6-אלקנים

Nomenclature of Cyclic Alkenes A number is not needed to denote the position of the functional group; it is always between C1 and C2. 6-אלקנים

Nomenclature of Alkenes 6-אלקנים

Nomenclature of Alkenes 6-אלקנים

Vinylic and Allylic Carbons vinylic carbon: the sp2 carbon of an alkene allylic carbon: a carbon adjacent to a vinylic carbon 6-אלקנים

Double Bonds Have Restricted Rotation Rotation about a double bond breaks the π bond. 6-אלקנים 12

Double Bonds Have Restricted Rotation Double bonds restrict rotation. 6-אלקנים

Six Atoms of an Alkene are in the Same Plane 6-אלקנים

Alkenes Have Cis–Trans Isomers Cis: The hydrogens are on the same side of the ring. Trans: The hydrogens are on opposite sides of the ring. They have different configurations; they can be separated. 6-אלקנים 15

Some Alkenes Do Not Have Cis–Trans Isomers 6-אלקנים

Cis–Trans Isomers Cis–trans isomers have different physical properties. 6-אלקנים

Which Is Cis and Which Is Trans? 6-אלקנים

The E,Z System of Nomenclature Z = Zusammen (together) E = Entgegen (opposite) 6-אלקנים

Relative Priorities The relative priorities of the two groups depends on the atomic numbers of the atoms attached to the sp2 carbon. 6-אלקנים 20

The E and Z Isomers 6-אלקנים

E and Z 6-אלקנים

E and Z 6-אלקנים

Isomers for Compounds with Two Double Bonds 6-אלקנים

Addition of Hydrogen Halides 6-אלקנים

Which sp2 Carbon Gets the H+? סיפוח HCl לפי כלל מרקובניקוב 6-אלקנים

The Mechanism Carbocation formation is the rate-limiting step. 6-אלקנים

Relative Stabilities of Carbocations 6-אלקנים

Carbocation Stability Alkyl groups decrease the concentration of positive charge on the carbon. 6-אלקנים

Hyperconjugation Stabilizes a Carbocation רשות 6-אלקנים

Stabilization by Hyperconjugation רשות 6-אלקנים

Hyperconjugation 6-אלקנים

It Looks Like What it is Closer To The Hammond postulate says that the transition state is more similar in structure to the species to which it is more similar in energy. 6-אלקנים

Why the Difference in Rate? The more stable carbocation is formed more rapidly. 6-אלקנים

The Difference in Carbocation Stability Determines the Products 6-אלקנים

What Product Will Be Formed? 6-אלקנים

The Electrophile Adds to the sp2 Carbon Bonded to the Most Hydrogens A regioselective reaction forms more of one constitutional isomer than another. 6-אלקנים

Not Regioselective 6-אלקנים

Acid-Catalyzed Addition of Water סיפוח מים בקטליזה חומצית לפי כלל מרקובניקוב 6-אלקנים

Mechanism for the Acid-Catalyzed Addition of Water 6-אלקנים

Acid-Catalyzed Addition of an Alcohol 6-אלקנים

Acid-Catalyzed Addition of an Alcohol Mechanism for the Acid-Catalyzed Addition of an Alcohol 6-אלקנים

The Major Product is a Surprise 6-אלקנים

The Major Product is a Surprise 6-אלקנים

Carbocation Rearrangement (a 1,2-hydride shift) שחלוף מרחיב טבעת 6-אלקנים

Carbocation Rearrangement (a 1,2-methyl shift) 6-אלקנים

The Carbocation Does Not Rearrange (No Improvement in Carbocation Stability) 6-אלקנים

Addition of HBr in the Presence of Peroxide ניתן לרשום על החץ Radical peroxide (ROOR) 6-אלקנים

Mechanism for the Addition of HBr in the Presence of Peroxide רשות 6-אלקנים

A Carbocation Intermediate is Not Formed, So a Carbocation Rearrangement Does Not Occur 6-אלקנים

Peroxide Effect Occurs Only with HBr עם HCl ו- HI הסיפוח רק מרקובניקוב. עם HBr הסיפוח גם מרקובניקוב וגם אנטי מרקובניקוב ( רדיקלי) 6-אלקנים

BH3 is an Electrophile 6-אלקנים

Hydroboration–Oxidation סיפוח מים אנטי מרקובניקוב THF ממס ניתן לרשום גם B2H6 במקוםBH3 6-אלקנים

The Electrophile Adds to the sp2 Carbon Bonded to the Most Hydrogens The reagents are numbered because the second set of reagents is not added until the first reaction is over. סיפוח מים מרקובניקוב סיפוח מים אנטי מרקובניקוב 6-אלקנים

Mechanism for Hydroboration 6-אלקנים

Addition of BH3 and Addition of HBr Follow the Same Rule 6-אלקנים

BH3 Has Three Potential Hydride Ions So a Dialkylborane and a Trialkylborane Can Be Formed 6-אלקנים

The Mechanism is the Same 6-אלקנים

OH Replaces BR2 6-אלקנים

Mechanism for the Oxidation Reaction רשות 6-אלקנים

No Carbocation Rearrangements 6-אלקנים

Addition of Br2 or Cl2 6-אלקנים

The Product is a Vicinal Dihalide 6-אלקנים

The Mechanism for the Addition of a Halogen The intermediate is a cyclic bromonium ion. 6-אלקנים

A Cyclic Bromonium Ion The carbons are the most electrophilic atoms. 6-אלקנים

No Carbocation Rearrangements 6-אלקנים

Alkenes Do Not Add I2 6-אלקנים

Formation of Halohydrins הברום נקשר לפחמן המכיל יותר מימנים ניתן לרשום HOX במקום X2 + H2O 6-אלקנים

Mechanism for Halohydrin Formation 6-אלקנים

Why Does it Follow the Same Rule? The electrophile adds to the sp2 carbon bonded to the most hydrogens. 6-אלקנים

More Reactions 6-אלקנים

Formation of an Epoxide 6-אלקנים

An Oxygen–Oxygen Single Bond is a Weak Bond 6-אלקנים

MCPBA is a Commonly Used Peroxyacid 6-אלקנים

Mechanism for Epoxidation רשות the mechanism is similar to that for the addition of Br2 6-אלקנים

Ozonolysis 6-אלקנים

Mechanism for Ozonide Formation רשות 6-אלקנים

The Ozonide is Converted to Ketones and/or Aldehydes 6-אלקנים

Ketones and Aldehydes 6-אלקנים

Ozonolysis 6-אלקנים

Ozonolysis 6-אלקנים

What Alkene Gave the Ozonolysis Products? 6-אלקנים

אוזונוליזה אם הפחמן של הקשר הכפול, קשור למימן, אזי מתקבל אלדהיד בתנאי חיזור, וחומצה קרבוקסילית בתנאי חימצון NaBH4 מחזר קרבוניל לכוהל שאלה פתרון 6-אלקנים

תגובה עם KMnO4 potassium permanganate: KMnO4 1,2-diols are also known as vicinal diols or vicinal glycols תנאים עדינים מנגנון: רשות סיפוח סין 6-אלקנים

תגובה עם KMnO4 -תנאים חריפים בתנאים חומציים או עם בסיס חם מתרחש ביקוע מחמצן אם פחמן הקשר הכפול, קשור למימן אחד מתקבלת חומצה קרבוקסילית אם פחמן הקשר הכפול, קשור לשני מימנים ( טרמינלי) מתקבל CO2 6-אלקנים

Addition of Hydrogen catalytic hydrogenation a reduction reaction 6-אלקנים

Mechanism for Hydrogen Addition רשות catalytic hydrogenation 6-אלקנים

Relative Stabilities of Alkenes The more substituents there are the greater the stabilization of the alkene Stability order due to two factors Hyperconjugation Stabilizing interaction between the C=C  bond and adjacent C-H σ bonds on substituents Bond strength A bond between an sp2 carbon and an sp3 carbon is somewhat stronger than a bond between two sp3 carbons 6-אלקנים

The Cis Isomer Has Steric Strain 6-אלקנים

The Relative Stabilities of Disubstituted Alkenes relative stabilities of dialkyl-substituted alkenes 6-אלקנים

The Product Does Not Have Stereoisomers 6-אלקנים

The Product is a Racemic Mixture When a reactant that does not have an asymmetric center forms a product that has one asymmetric center, the product is a racemic mixture. 6-אלקנים

Formation of a Racemic Mixture 6-אלקנים

Formation of a Second Asymmetric Center When a reactant that has an asymmetric center forms a product that has new asymmetric center, the product is a pair of diastereomers. 6-אלקנים

Only Syn Addition 6-אלקנים

Syn Addition to a Cis Isomer Forms Only the Erythro Stereoisomers 6-אלקנים

If the Substituents are the Same, the Erythro Stereoisomer is a Meso Compound 6-אלקנים

Syn Addition to a Trans Isomer Forms Only the Threo Stereoisomers 6-אלקנים

תרגיל-סיפוח מימן לקשר כפול- סין שאלה A מתקבל יותר, דיאסטריומרים תשובה 6-אלקנים

Syn Addition to a Cis Isomer Forms Only the Cis Stereoisomers 6-אלקנים

Syn Addition to a Trans Isomer Forms Only the Trans Stereoisomers 6-אלקנים

If the Substituents are the Same, the Cis Stereoisomer is a Meso Compound 6-אלקנים

Only Syn Addition 6-אלקנים

to the Same Side of the Ring The H and OH Add to the Same Side of the Ring 6-אלקנים

Addition of a Halogen is an Anti Addition 6-אלקנים

Anti Addition to a Cis Isomer Forms Only the Threo Stereoisomers 6-אלקנים

If the Substituents are the Same, the Cis Stereoisomer is a Meso Compound 6-אלקנים

If the Substituents are the Same, the Erythro Stereoisomer is a Meso Compound 6-אלקנים

Anti Addition to a Cis Isomer Forms Only the Trans Stereoisomers 6-אלקנים

An Enzyme Forms One Stereoisomer; It is Completely Stereoselective 6-אלקנים

An Enzyme Can Block One Side of the Reactant 6-אלקנים

An Enzyme Reacts with Only One Stereoisomer; It is Completely Stereospecific 6-אלקנים

Compounds That Can Be Formed from an Alkene 6-אלקנים

antioxidants( העשרה) Two examples of radical inhibitors that are present in biological systems are vitamin C and vitamin E. Like hydroquinone, they form relatively stable radicals. Vitamin C (also called ascorbic acid) is a water-soluble compound that traps radicals formed in the aqueous environment of the cell and in blood plasma. Vitamin E (also called  -tocopherol) is a water-insoluble (hence fat-soluble) compound that traps radicals formed in nonpolar membranes. Why one vitamin functions in aqueous environments and the other in nonaqueous environments should be apparent from their structures , which show that vitamin C is a relatively polar compound, whereas vitamin E is nonpolar 6-אלקנים