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(a)
Interpretation:
How the given lithium dialkylcuprate reagent can be synthesized from an alkyl, alkenyl, alkynyl, or aryl halide is to be shown.
Concept introduction:
A lithium dialkylcuprate is synthesized from the corresponding alkyllithium reagent by treating it with copper(I) iodide, CuI. Because the metal-bonded C atom bears a partial negative charge on both the alkyllithium reagent and the lithium dialkylcuprate, umpolung technically does not occur in this reaction, but synthesizing a lithium dialkylcuprate from an
(b)
Interpretation:
How the given lithium dialkylcuprate reagent can be synthesized from an alkyl, alkenyl, alkynyl, or aryl halide is to be shown.
Concept introduction:
A lithium dialkylcuprate is synthesized from the corresponding alkyllithium reagent by treating it with copper(I) iodide, CuI. Because the metal-bonded C atom bears a partial negative charge on both the alkyllithium reagent and the lithium dialkylcuprate, umpolung technically does not occur in this reaction, but synthesizing a lithium dialkylcuprate from an alkyl halide does represent polarity reversal at the C atom. The C atom bonded to Cu should be bonded to halide. The carbon atom of C-X bond is electron poor whereas the carbon of C-Cu bond is electron rich.
(c)
Interpretation:
How the given lithium dialkylcuprate reagent can be synthesized from an alkyl, alkenyl, alkynyl, or aryl halide is to be shown.
Concept introduction:
A lithium dialkylcuprate is synthesized from the corresponding alkyllithium reagent by treating it with copper(I) iodide, CuI. Because the metal-bonded C atom bears a partial negative charge on both the alkyllithium reagent and the lithium dialkylcuprate, umpolung technically does not occur in this reaction, but synthesizing a lithium dialkylcuprate from an alkyl halide does represent polarity reversal at the C atom. The C atom bonded to Cu should be bonded to halide. The carbon atom of C-X bond is electron poor whereas the carbon of C-Cu bond is electron rich.
(d)
Interpretation:
How the given lithium dialkylcuprate reagent can be synthesized from an alkyl, alkenyl, alkynyl, or aryl halide is to be shown.
Concept introduction:
A lithium dialkylcuprate is synthesized from the corresponding alkyllithium reagent by treating it with copper(I) iodide, CuI. Because the metal-bonded C atom bears a partial negative charge on both the alkyllithium reagent and the lithium dialkylcuprate, umpolung technically does not occur in this reaction, but synthesizing a lithium dialkylcuprate from an alkyl halide does represent polarity reversal at the C atom. The C atom bonded to Cu should be bonded to halide. The carbon atom of C-X bond is electron poor whereas the carbon of C-Cu bond is electron rich.
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Chapter 19 Solutions
Organic Chemistry: Principles And Mechanisms (second Edition)
- One method for the analysis of Fe3+, which is used with a variety of sample matrices, is to form the highly colored Fe3+–thioglycolic acid complex. The complex absorbs strongly at 535 nm. Standardizing the method is accomplished using external standards. A 10.00-ppm Fe3+ working standard is prepared by transferring a 10-mL aliquot of a 100.0 ppm stock solution of Fe3+ to a 100-mL volumetric flask and diluting to volume. Calibration standards of 1.00, 2.00, 3.00, 4.00, and 5.00 ppm are prepared by transferring appropriate amounts of the 10.0 ppm working solution into separate 50-mL volumetric flasks, each of which contains 5 mL of thioglycolic acid, 2 mL of 20% w/v ammonium citrate, and 5 mL of 0.22 M NH3. After diluting to volume and mixing, the absorbances of the external standards are measured against an appropriate blank. Samples are prepared for analysis by taking a portion known to contain approximately 0.1 g of Fe3+, dissolving it in a minimum amount of HNO3, and diluting to…arrow_forwardAbsorbance and transmittance are related by: A = -log(T) A solution has a transmittance of 35% in a 1-cm-pathlength cell at a certain wavelength. Calculate the transmittance if you dilute 25.0 mL of the solution to 50.0 mL? (A = εbc) What is the transmittance of the original solution if the pathlength is increased to 10 cm?arrow_forwardUnder what conditions will Beer’s Law most likely NO LONGER be linear? When the absorbing species is very dilute. When the absorbing species participates in a concentration-dependent equilibrium. When the solution being studied contains a mixture of ions.arrow_forward
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- Each of the highlighted carbon atoms is connected to hydrogen atoms.arrow_forwardく Complete the reaction in the drawing area below by adding the major products to the right-hand side. If there won't be any products, because nothing will happen under these reaction conditions, check the box under the drawing area instead. Note: if the products contain one or more pairs of enantiomers, don't worry about drawing each enantiomer with dash and wedge bonds. Just draw one molecule to represent each pair of enantiomers, using line bonds at the chiral center. More... No reaction. Explanation Check O + G 1. Na O Me Click and drag to start drawing a structure. 2. H + 2025 McGraw Hill LLC. All Rights Reserved. Terms of Use | Privacy Center | Accessibility 000 Ar Parrow_forwardDraw a tetramer of this alternating copolymer.arrow_forward
Organic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage Learning