__ is the singly most imp. factor ind etermining E1 or E2. IWhy?
nature of base
strong base--> rate of bimolecular reaction will be greater than the rate of ionizatio= E2
no strong base= good solvent makes a unimoelcular ioniization likely; loss of proton of weak base--> E1
E1: base strength unimportant
E2: requires strong bases
The slow step of the E1 reaction is __. Like SN1 E1 critically depends on __.
In the E2 reaction, the TS spreads out the __ of the base over the entire molecule. There is no more good for __ in the E2 TS than in the reactants. The E1 is less sensitive tot eh __; in fact, some reagents are stronger bases in __.
formation of two ions
polar ionizing solvents
less polar solvents
Summarize solvent comparison and substraet.
E1: requries good ionizing solvent
E2: solvent polarity not as imp.
E1 and E2: tertiary > secondary > primary (primary will not go E1)
In the E1 reaction, the __ is formation of a carbocation, and the reactivity order reflects the stability of __. In the E2 reaction, the more __ generally form more substituted, more stable alkenes.
The rate of the E1 is proportional to the __, but not to the __. It is a __.
The rate of the E2 is proportional to __. It followsa __/
concentration of hte alkyl halide (RX)
concentration of the base
1st order rate eq.
both the alkyl halide and base
second order rate eq.
In most E1 and E2 elims with two or more possible products, the product with the most __ predominates, called __, adn the most highyl subbed product is __.
subbed double bond
The E1 reaction begins with an __ to give a __. No particular geometry required. The E2 reaction takes place through a concerted mechanism that requires a __ arrangement of hte bonds to the atoms being eliminated. Th TS is usually __, but can be __ in rigid systems
E1 reactions invove a __, which can __ usually by the shift of a __ or an __, to give a more stable carbocation.
The E2 takes place in __ with __. __ is possible in E2.