You may sometimes find it desirable to conjoin a passive verb form with a passive infinitive, as in
The building is scheduled to be demolished next weekand
The piece was originally intended to be played on the harpsichord.These sentences are perfectly acceptable. But it’s easy for things to go wrong in these double passive constructions. They sometimes end in ambiguity:
An independent review of the proposal was requested to be made by the committee.In this sentence, is the committee making the request or doing the review? What is worse, double passives often sound ungrammatical, as this example shows:
The fall in the value of the Yen was attempted to be stopped by the Central Bank.
How can you tell an acceptable double passive from an unacceptable one? If you can change the first verb into an active one, making the original subject its object, while keeping the passive infinitive, the original sentence is acceptable. Thus you can say
The city has scheduled the building to be demolished next weekand
The composer originally intended the piece to be played on the harpsichord.But you cannot make similar changes in the other sentence. You cannot say
The Central Bank attempted the fall in the value of the Yen to be stopped.
This is all rather technical, however, and it may be easiest just to trust your ear. If a double passive sounds tinny, rewrite the sentence.