1. What is the expected product melting point if the bromination of stilbene by PHPB is...
alswering these questions. 1. If the bromination of trans-stilbene proceeded by syn addition what isomer(s) of stilbene dibromide would be formed? 2. If the bromination of trans-stilbene proceeded by anti addition what isomer(s) of stilbene dibromide would be formed? 3. Which isomer(s) of stilbene dibromide would be formed if the reaction followed Mechanism 4? Mechanism 4: Bromination is a multi-step process. In this mechanism, the pi bond attacks the bromine molecule as in Mechanism 1. Some time after the carbocation...
Look up and draw the mechanism for the addition of Br2 to double bonds. Reference the source from which you acquired the mechanism. Give the IUPAC name of the major product in the above-mentioned reaction. Draw the major product of obtained in the addition of Br2 to stilbene. Is this isomer chiral? What would be the optical rotation if this sample was placed in a polarimeter? Would a student obtain the same product if you started with cis-stilbene instead of...
Consider the bromination of cis-stilbene. What product(s) are expected? What is the stereochemical relationship of those products to the product(s) you synthesized from trans- stilbene?
From the lab hand-out: “In this experiment, you will synthesize stilbene dibromide by reacting the alkene, trans-stilbene, with Br2 formed in situ from pyridinium tribromide (Figure 1). This reaction takes place and produces two stereocenters, therefore up to three products can be formed; S,S and R,R enantiomers and/or racemic mixture of R,S and S,R which are meso compounds (by definition a meso compound is a molecule with multiple stereocenters that is superimposable on its mirror image)…” After you complete your...
help with melting point and pure product. thank you Bromination of Stilbene lab would my product be pure and why based on the following data Melting point Crude: 236.4 - 240.2 ℃ Product 238.7-239.9 ℃ Lit melting point: 235-241℃
please help with number 6! 1.(2) What is the meaning of “E” in E-stilbene? 2.(4) What functional groups are present in E-stilbene? 3.(2) Write the reaction that occurs between E-stilbene and bromine. 4.(4) Write the mechanism for the addition of bromine to €- stilbene to give meso-stilbene dibromide via the intermediate cyclic bromonium ion. 5.(2) Which reagent, E-sitlbene or bromine, acts as the nucleophile in this reaction? Which reagent is the electrophile? 6.(4) Calculate the theoretical yield of meso-stilbene dibromide...
please help with filling out this table and answering 8 questions Data Table Br H CH2CH3OH N-H Bry Chemicals H (E)-Stilbene Ethanol Pyridinium tribromide CsH.Br3N Stilbene Dibromide C14H12Br2 Molecular Formula C14H12 CHO Molecular Weight 180.25 g/mol 46.07 g/mol 319.82 g/mol 340.06 g/mol Physical Properties White solid Clear liquid White solid White solid Melting Point 122-124 °C N/A 127-133 °C 241-243 °C Amount needed 0.25 g 10 mL 0.5 g Mole needed 1.39 mmol 1.56 mmol Amount Used Moles Used Amount...
help with limiting reagents and percent yield needed the reactions are the bromination of cis-stilbene and trans-stilbene. The reagents and the moles of each reagent are in my data, as is the moles of the products formed. The volume and mass of the reagents are given as well. I need to know how to find the percent yield and what the limiting reagents are for both the trans and cis stilbene brominations. The information is there. Name Physical Properties of...
1. Bromination of an alkene is restricted to a syn addition. In this problem you will design an experiment to validate or provide evidence that alkene bromination undergoes syn addition You will use the following starting alkene a) trans-stilbene b) cis-stilbene A. Draw the mechanisms showing all electron flows (curved arrows) and the cyclic halonium intermediate to predict the stereochemical products of the bromination reaction for (a) trans-stilbene and (b) cis-stilbene formed from syn addition. B. Design the experiment to...
1) Write a stepwise mechanisms for the bromination of: a) trans-stilbene and b) cis-stilbene (substitute benzene rings by Ph-notation for convenience; e.g., stilbene could be written as Ph- CH=CH-Ph). I 2) Use (S) and (R) nomenclature to label all stereogenic centers in the above products (each has two stereogenic centers) in problem 1. Identify any enantiomers and meso-products. 3) Complete the following table including formula weights and grams and moles of reagents used in order to calculate a theoretical yield...